AN ABSTRACT OF THE THESIS OF
Kathryn Grace Busse for the degree of Master of Science in Rangeland Resources presented on December 20, 1988
Title: ECOLOGY OF THE SALIX AND POPULUS SPECIES OF THE
CROOKED RIVER NATIONAL GRASSLAND
Abstract approved: Redacted for Privacy tirluffman
Riparian communities dominated by members of the
Salicaceae (Salix lasiandra, S. lutea, S. lemmonii,
Populus trichocarpa, P. tremuloides and S. exigua) were studied at the Crooked River National Grassland in central Oregon. The objectives of this study were to examine the relationships between the Salix and Populus species and microsite to identify the principal environmental gradients that may determine the distribution of these species. One hundred twenty five stands of riparian vegetation dominated by the above members of the Salicaceae were intensively sampled. A predetermined set of physical variables were collected to characterize their habitats.
These variables included surface soils, stream characteristics, vegetative characteristics, and other physiographic variables. Canonical discriminant function analysis was used to separate the Salix and Populus species based on the set of 19 environmental variables stratified according to size class (i.e. sapling, intermediate and decadent).
The Salicaceae, as a family, occupy specific habitats in terms of surface soil characterisitics. The Salicaceae require surface soils which have a mean pH of 7.3, a mean macroporosity of 27.08%, a mean sand content of 53.42%, a mean organic matter content of 6.0%, a mean coarse material content of 28.59%, and a mean organic horizon of
0.58 cm. The remaining physical variables change for each species.
The variables which most readily separated the species were stream gradient and average stand distance from the wetted channel. These two variables represented an environmental gradient of depth to an effective water table in relation to headwater versus valley-bottom stream systems. P. tremuloides and S. lemmonii occupy areas of steep stream gradient (headwater areas) and deep water tables (more xeric microsites). Conversely, S. lasiandra,
S. lutea, S. exigua and P. trichocarpa occupy areas of lesser stream gradient (valley bottoms) and higher water tables (more mesic microsites). Ecology of the Salix and Populus Species of the Crooked River National Grassland
by
Kathryn Grace Busse
A THESIS
submitted to
Oregon State University
in partial fulfillment of the requirements for the degree of
Masters of Science
Completed December 20, 1988
Commencement June 1989 APPROVED:
Redacted for Privacy Rangeland\Recesin charge of major
Redacted for Privacy Head of department pt Ranggiand Resources
Redacted for Privacy Dean of e gchool <1
Date thesis is presented December 20, 1987 ACKNOWLEDGEMENTS There are various and sundry people who contributed to the completion of my thesis. All of these people helped me physically, spiritually and emotionally at sometime during the whole masters' process.
Thanks to my parents, Ken and Harriette, my brother
Steven and sister Karen, for your unconditional love and support. Even though you did not and may still not quite understand how I got from my time with you to where I am now, you continue to understand, encourage and love me. Thanks to my major professor, Boone. Though we argued and disagreed, you helped me get through graduate school.
Those strong cups of coffee really helped! Thank you also, to the rest of my committee members - Dave, Lee and John, each of whom contributed to my thesis project in a significant manner.
Thanks to all the folks at the 'Lands'. Frank, Byron,
Kevin, Brian and Dave all at sometime or another hiked to some remote area to help me locate and sample some willow, aspen or cottonwood site. You people helped me to remain sane during the course of my co-op and thesis project period.
Thanks to all the people at the Range Department. My fellow graduate students were always willing to listen, commiserate and eventually laugh. We were all able to survive and eventually return to the outside world. Lastly, thanks to Matt: my friend, lover, confidante, troubleshooter and hit man. You encouraged me to return to academia, and then understood when I couldn't take it anymore. I don't see how you survived me, though I'm certainly happy and lucky you did. TABLE OF CONTENTS
Page
INTRODUCTION 1
OBJECTIVES 4
STUDY AREA 5
Location 5
Geology and Physiography 7
Climate 9
Vegetation 11
LITERATURE REVIEW 13
Importance of Riparian Zones 14
Wildlife 14
Fisheries and Aquatic Ecosystems 14
Livestock 16
Riparian Vegetation and the Physical Environment 18
METHODS 21
Reconnaissance 21
Vegetation 22
Water 25
Soils 25
Other Data 27
Data Analysis 28 RESULTS 30
Analysis of Salix and Populus Habitat 30
Sapling Size Individuals 30
Intermediate Size Individuals 38
Decadent Individuals 46
DISCUSSION 55
Population Structure 55
Habitat Changes Through Time 60
Salix lasiandra 61
Salix lutea 63
Populus tremuloides 65
Salix exiqua 67
Management Implications 69
CONCLUSIONS 73
LITERATURE CITED 76
APPENDICES
Appendix A. Dominant Species Identification 82
Appendix B. Plant Species 86
Appendix C. Acronyms of the Physical Variables 94
Appendix D. Discriminant Function Scores 97
Appendix E. Values of the Physical Variables 101 LIST OF FIGURES
Figures Page
1 Study area location (shaded area). 6
2 Bedrock types of the Crooked River National 8 Grassland.
3 Plot of canonical discriminant functions 1 36 and 2 for sapling size individuals.
4 Plot of canonical discriminant functions 1 44 and 2 for intermediate size individuals.
5 Plot of canonical discriminant functions 1 54 and 2 for decandent size individuals.
6a Diameter class distribution of the Salicaceae 56 present prior to exclosure construction (n=66).
6b Current diameter class distribution of the 56 Salicaceae in exclosures (n=125).
7 Diameter class distribution of Populus 58 trichocarpa. LIST OF TABLES
Table Page
1 Monthly mean temperatures and precipitation 10 for the Crooked River National Grassland.
2 Classification by diameter range and 23 approximate age of the Salicaceae.
3 Means and test statistics (ANOVA) associated 31 with physical variables of the sapling size class.
4 Summary of canonical discriminant function 34 analysis of physical variables for the sapling size class.
5 Mahalanobis' distances between group 37 centroids for the sapling size class.
6 Means and test statistics (ANOVA) associated 40 with physical variables of the intermediate size class.
7 Summary of canonical discriminant function 43 analysis of physical variables for the intermediate size class.
8 Mahalanobis' distances between group 45 centroids for the intermediate size class.
9 Means and test statistics (ANOVA) associated 47 with physical variables of the decadent size class.
10 Summary of canonical discriminant function 51 analysis of physical variables for the decadent size class.
11 Mahalanobis' distances between group 53 centroids for the decadent size class.
12 Means of the physical variables 62 associated with SALIX LASIANDRA.
13 Means of the physical variables 64 associated with SALIX LUTEA. Table Page
14 Means of the physical variables associated 66 with POPULUS TREMULOIDES.
15 Means of the physical variables associated 68 with SALIX EXIGUA. ECOLOGY OF THE SALIX AND POPULUS SPECIES OF THE CROOKED RIVER NATIONAL GRASSLAND
INTRODUCTION
A wide diversity of natural resource values are
associated with riparian ecosystems. These values include recreation, timber, water, fisheries, wildlife, aesthetics
and livestock grazing (Thomas et al. 1979, Johnson and
Carothers 1982, Claire and Storch 1983, Kauffman and
Krueger 1984). Because of the multiple values of these
areas, riparian zones have become a controversial focal
point of land management. This focus has concentrated on
the deterioration of these ecosystems, especially in the
semi-arid and arid rangelands of the Western United States
(Davis 1982, Boles and Dick-Peddie 1983, Medina 1986). The
decline in the productivity of riparian zones has become a prime concern to scientists, the livestock industry and the concerned public. Much of the rhetoric discussed on the subject of riparian management has been based on opinion, hearsay or personal bias rather than conclusions drawn from scientific research (Kauffman and Krueger
1984) .
In riparian ecosystems of semi-arid regions, members of the Salicaceae (Populus and Salix spp.) are critical sources of diversity for many wildlife species (Thomas et al. 1979, Kauffman and Krueger 1984 and Kauffman 1988). In rangeland ecosystems, they are often the only arboreal 2
species present. The highest densities of noncolonial breeding birds ever reported were in cottonwood-dominated
riparian communities of Arizona (Johnson et al. 1977).
When woody species are eliminated from the riparian zone,
habitat quality declines for those species which require
the arboreal riparian species. Shade from these arboreal species also acts in the modification of the stream/riparian microclimate thereby facilitating the survival of many native aquatic and terrestrial species, both plant and animal (Cummins 1974 and Everest et al.
1985).
In order to improve riparian structure and productivity, additional knowledge of the ecology of riparian plant species is necessary. Therefore,
autecological studies are warranted. Because of the value to fisheries, wildlife, livestock and aesthetics, woody riparian species, especially of the Salicaceae family, are receiving increased attention from land managers as well as the scientific community. To date, there has been a scarcity of published scientific research on the basic autecology of the Salicaceae.
In this study, the autecology of Salix lasiandra
Benth., S. lutea Nutt., S. lemmonii Bebb, Populus trichocarpa (Torr. & Gray Ex Hook), P. tremuloides
(Michx.) Loeve & Loeve and S. exigua Nutt. will be examined. These species are intimately associated with the presence of free water, and are therefore termed riparian 3
obligates (Kovalchik 1986). The ecology of these species is not well understood, although the ecology of P. trichocarpa and P. tremuloides has been more intensively
studied (Glinski 1977 and Pielou et al. 1986) than that of the Salix species. This research study proposes to examine
the aforementioned Populus and Salix species in time and space at the Crooked River National Grassland (CRNG) in
central Oregon. Specifically, habitat conditions and the population structure of these important species will be examined. 4
OBJECTIVES
The riparian species examined in this study are Salix lasiandra Benth., S. lutea Nutt., S. lemmonii Bebb,
Populus trichocarpa (Torr. & Gray Ex Hook), P. tremuloides
(Michx.) Loeve & Loeve and S. exigua Nutt. The studyarea was located at the Crooked River National Grassland (CRNG)
in central Oregon. The objectives of this study were:
1. To examine the relationships between Salix and Populus
species and microsite, in order to identify the principal
environmental gradients that may determine the distribution of the above species (i.e. a spatial gradient).
2. To quantitatively describe microsites occupied by the above species within a chronosequence (i.e. a temporal gradient).
3. To quantify the population structure by size class of the above Salicaceous species. 5
STUDY AREA
Location
The Crooked River National Grassland (CRNG) isone of the five districts of the Ochoco National Forest, Oregon.
The Grassland lies to the east of the Cascade Mountains of
central Oregon with the majority occurring east of the
Deschutes River (Figure 1). Topography of the CRNG is gently rolling hills and low buttes separated by wide
flats. There are deep canyons along the Deschutes and
Crooked Rivers, in addition to less dramatic canyon relief along Squaw and Willow Creeks. The western portion of the
Grassland is plateau-like while the eastern part is gently rolling, low mountainous land with the greatest relief at the southern boundary (Hopkins and Kovalchik 1983).
On the portion of the CRNG which lays to the east of the Deschutes river, tributaries feed into Willow Creek, which eventually enters the Deschutes River south of Warm Springs, Oregon.
Elevation ranges from 683 meters near Madras to 1557 meters on Gray Butte. The riparian areas that were sampled ranged in elevation from 866 meters at Haystack Reservoir to 1207 meters feet on the west side of Grizzly Mountain.
This range represented the entire elevational gradient over which the riparian ecosystems of the CRNG occurred. 6
0 137 Scale in kilometers
Figure 1. Study area location (shaded area). 7
Geology and Physiography
The Deschutes river flows through the John Day and the Clarno Formations. The rock exposures found along the
canyon walls of the Deschutes were restricted to formation
during the Miocene (Orr and Orr 1985). Present in the portion of the Deschutes river canyon which flows though John Day materials are numerous prehistoric landslides, which created debris clogs causing high stream velocities and rapids throughout the length of the river. The area of the river influenced by the Clarno Formation is dominated by the presence of rhyolitic ash.
The Crooked River National Grassland is in the southwestern corner of the Columbia Basin Physiographic
Province (Franklin and Dyrness 1973). The main portion of the Columbia Basin Province was formed due to geologic events which occurred during the Miocene era. During this time, a large outpouring of lava flowed to form the
Columbia River Basalts. The formation is from 600 to 1500 meters in total thickness, with isolated flows from 8 to 30 meters thick (Franklin and Dyrness 1973). The Columbia
River Basalts are extensivley covered by Plio-Pleistocene deposits, typified by the Palouse loess. A general view of the bedrock types of the CRNG (Paulson 1977) may be seen in Figure 2. 8
Sedimentary rocks
Highly weatheredtuffaceous sediments
Basalts andandesites
the Crooked RiverNational Figure 2. Bedrock types of Grassland. 9
Climate The mean monthly temperatures and precipitation at
two locations near the study area are given in Table 1.
The majority of precipitation comes mainly as snow during
the winter months. Temperatures tend to be moderate (-1.8 to 20.3 °C) throughout the year (Table 1). The frost-free
season is very short with the average growing season approaching only 100 days. Frost can occur any month of the year (Paulson 1977). 10
Table 1. Monthly mean temperatures (°C) and precipitation (mm) for the Crooked River National Grassland.
Madras Grizzly Location: (Elev.688 m) (Elev. 1109 m)
Temp. Precip. Temp. Precip. Month (30 yrs.) (10 yrs.) (15 yrs.) (10 yrs.)
January -1.1 32.3 -1.8 35.8
February 1.9 28.7 1.1 33.0
March 4.8 25.1 2.8 35.1
April 8.4 15.0 6.7 21.3
May 12.5 33.8 10.8 53.8
June 16.1 21.6 14.0 31.8
July 20.3 9.1 18.5 6.1
August 19.0 6.9 17.4 9.9
September 15.2 10.4 14.5 16.5
October 9.5 15.7 8.9 29.0
November 3.7 34.5 3.5 41.7
December 1.0 34.0 1.0 40.6
ANNUAL 9.2 267.2 8.1 354.6 11
Vegetation Arboreal or shrub-dominated riparian communities of the CRNG are predominantly influenced by Salix lasiandra,
S. lutea, S. lemmonii, Populus trichocarpa, P. tremuloides and S. exigua. The remaining communities are dominated by various Carex, Juncus and graminoid species. The major
understory dominants in the Salix and Populus communities
include Poa pratensis L., Agrostis alba L., Juncus
ensifolius Wikst., Achillea millefolium L., Epilobium
qlabberimum Barbey andMimulus quttatus DC. As of 1988 on the CRNG, 372 hectares of the estimated
958 hectares of riparian zones, creeks and springs, (81%) have been closed to cattle grazing through the
construction of corridor fencing. To date, of the total
89.1 kilometers of riparian fence designated to be
constructed, 58.7 kilometers (66%) have been completed.
The upland vegetation of the Crooked River National Grassland falls into the juniper-sagebrush-bunchgrass zone
(Franklin and Dyrness 1973). Upland vegetation associated
with the riparian zones of this area are dominated by
. Juniperus occidentalis Hook. (western juniper) and
Artemisia tridentata Nutt. (big sagebrush). Areas of
higher elevation are dominated by Pinus ponderosa Dougl.
Ex P.& C. Lawson (ponderosa pine).
A large portion of the CRNG, primarily abandoned
croplands, were seeded to Agropyron cristatum (L.) Gargth.
(crested wheatgrass), Agropyron spicatum (Pursh) Scribn. 12
and Smith (bluebunch wheatgrass) and Agropyron inerme (Scribn. and Smith) Rydb. (beardless bluebunch wheatgrass). These species occur on approximately 24,282 hectares of the total 45,326 hectares (54%) which comprise
the CRNG. The majority of this seeding was done around 1960 when the Forest Service assumed the management responsibility of this area. 13
LITERATURE REVIEW
The definition of riparian zones has becomemore
precise over time as a result of increased research,even though a single definition is not universally accepted. The simplest definition of riparian vegetation is
"vegetation rooted at the water's edge" (Campbell and
Franklin 1979). A more precise definition is: "areas where
soil moisture is sufficiently high to support unique plant
and animal communities that differ from the surrounding drier uplands" (Johnson and Carothers 1982). The inherent diversity of these ecosystems is a result of "assemblages of plant, animal and aquatic communities whosepresence can be either directly or indirectly attributed to factors that are stream-induced or related" (Kauffman and Krueger
1984). The definition proposed by Carter (1978) has been chosen as the most appropriate: "those areas associated with streams, lakes and wet areas where plant communities are predominantly influenced by their association with water".
Riparian zones within the rangelands of the West have the following in common: (1) they create well-defined habitat zones within the much drier surrounding areas;
(2) they make up a minor proportion of the overall area;
(3) they are generally more productive in terms of biomass plant and animal -- than the remainder of the area and (4) they are a critical source of diversity
(Thomas et al. 1979). 14
Importance of Riparian Zones Wildlife
The importance of riparian zones for wildlife habitat
is well documented (Johnson et al. 1977, Thomas etal. 1979, Stauffer and Best 1980, Krausman et al. 1985).
Riparian habitats support many of the wildlife species of
North America: 42% of mammals, 38% of birds, 33% of reptiles and 13% of amphibians (Hubbard 1977). Thomaset al. (1979) stated that 299 out of 363 species present in the Great Basin of southeast Oregon utilized riparian habitat at some time in their life cycle. They suggested that the reasons riparian zones are so important toso many species of wildlife are:(1) the presence of water lends to an increased occurrence of food, cover and water for use by wildlife; (2) the availability of watercauses an increase in plant biomass, especially of those species dependent on high amounts of available water; (3) the exhibition of "edge effect" creates structural diversity and (4) the microclimate attracts wildlife species.
Fisheries and Aquatic Ecosystems
Fish depend on riparian ecosystems for their survival and growth, due to the water temperature regulating abilities of the riparian vegetation. In lower order
(headwater) streams, this relationship is especially critical. Anadromous salmonids require cool, moving water, clear migration routes to the ocean, particular gravel bed 15
characteristics for spawning, adequate water quality
(related to sediment load and dissolved oxygen content),
instream cover and organisms for food (Everest et al.
1985). Resident species have many of the same requirements (Wesche et al. 1985).
Vegetation bordering streams, along with undercut banks and woody debris, provides cover for fish (Armour 1978). It also provides habitat for terrestrial and aquatic insects which are a substantial portion of the
fish diet, and allochthonous inputs into theenergy pool of the aquatic ecosystem as a whole (Cummins 1974).
Vegetation also acts to moderate stream temperature fluctuations over the seasons (Everest et al. 1985). Streambanks vegetated by herbaceous and/or woody species are better able to dissipate the energy of accelerated stream velocities than are unvegetated streambanks due mostly to the anchoring abilities of roots
(Brinson et al. 1981). Armour (1978) stated that this function is similar to that of streambank protection from ice floes, large woody debris and animal trampling. 16
Livestock
Cattle are attracted to riparian zones formany of the same reasons that wildlife speciesare. These include the availability of water, a more desireable microclimate,
relatively level topography and the quality and variety of
forage (Kauffman and Krueger 1984). Cattle may spendmore than half of their time in the riparian zone where microclimate tends to be more favorable (Bryant 1982).
Roath and Krueger (1982) stated that an eastern Oregon riparian zone accounted for 1.9% of the total allotment and produced about 21% of the total available forage.
Eighty-one percent of the total herbaceous vegetation utilized by the cattle was from the riparian zone.
Cattle grazing is the most extensive land use of the interior Pacific Northwest (Skovlin 1977). The majority of literature on riparian zones in semi-arid and arid rangelands suggests that improper grazing by livestock is the primary source of riparian degradation. Many different authors working in a variety of riparian ecosystems have offered solutions to the problem. These range from total exclusion to various manipulations of the animals through changes in management. Total exclusion of livestock from the riparian zone is a restorative practice that has been instituted on many streams (Davis 1982). This exclusion is achieved by fencing the entire riparian zone. Several authors have suggested that livestock exclusion is the only known method of riparian rehabilitation in which 17
functioning, reproducing riparian zonesare perpetuated (Davis 1982, Platts 1985, Stuber 1985). Though not without problems, many land managers have also come to view this practice as their only choice for natural riparian
rehabilitation. However, this conflicts withone of the current major uses of the semi-arid rangelands of the
West: livestock grazing. Therfore, it may not be feasible to all riparian zone managers.
Improving the productivity and structural complexity of riparian zones without the removal of livestock may be an alternative. Authors have suggested that changing the season of grazing in these areas helps to reduce the adverse effects of cattle use (Marlow and Pogacnik 1985).
Others stated that the degree of utilization is the key to
"successful" grazing of riparian zones. In a Montana riparian ecosystem, Marlow and Pogacnik (1985) reported that little or no degradation of riparian habitats occurred if utilization was 20% or less. Bryant (1985), working in an Oregon riparian area speculated that riparian productivity would increase if forage utilization was less than 70%. Many cattle producers agree with this approach because the riparian zone is often the highest forage producing area of the pasture, and the only place for cattle to water (Swan 1979). Grazing management strategies for riparian zone rehabilitation and/or maintenance include specialized grazing systems, managing riparian zones as special use pastures, and several basic 18
range management practices (e.g. salting, artificial
reestablishment of riparian species, upland water
development and herding (Bryant 1982, Davis 1982, Kauffman
et al. 1983, Platts and Nelson 1985). A grazing strategy which may promote riparian recovery should allow for the recovery of both biological and physical components of the
riparian system (Elmore and Beschta 1987).
Riparian Vegetation and the Physical Environment
Quantification of the occurrence of vegetation along any given environmental continuum is an interesting approach to the study of vegetation ecology (Johnson and
Lowe 1985, Warren and Anderson 1985). This approach has been applied to the study of riparian vegetation,even though difficulty often arises in establishing causal relationships between the distribution of species and environmental factors (Merry et al. 1981, Warren and Anderson 1985).
Research concerning the vegetation-environmental relationships of the Saskatchewan River riparian ecosystem has resulted in the identification of some pertinent environmental factors that influence vegetation distribution. Walker and Coupland (1968) concluded that the two overriding factors responsible for species presence were a combination of anthropogenic disturbance factors (i.e. mowing and water table fluctuation due to 19
change in water depth or soil moisture). The effects of disturbance resulted in a competitive advantage forsome species over others (i.e. Scolochloa festucacea practically eliminated Carex atherodes when the disturbance was mowing). Water level fluctuationwas also found to influence species presence (i.e. Senecio congestus was a dominant in the spring and decreased by mid-July which in this case was attributed to seasonal change - a temporal gradient). Dirschl and Coupland (1972) found that the moisture regime (nature of the water supply - water depth class for mid-June and August), position and stability of the water table over the growingseason, nutrient status and pH were the most significant physical factors related to species distribution. They concluded that the most applicable physical characterizationcan be attained through recognition of "landform" (i.e. bog, aquatic, fen, alluvial levee or wooded fen) and "drainage patterns" (i.e. moisture gradient).
Similar results were found by Merry et al. (1981)on the River Wye in Wales. They found that gradients associated with length of growing season such as, pH, nutrient levels and river flow were the significant environmental components affecting vegetation abundance and distribution. A subsequent study encompassing a larger land area in Wales produced different results (Curry and
Slater 1986). They concluded that the major environmental 20
factors influencing vegetation distribution appearedto be altitude, intensity of shade and soil nutrient status. In a study on the distribution of Salix species in
Wyoming, Patten (1968) described a correlation between physical factors and species occupancy. He found that relative proximity to the river and therefore soil moisture, influenced growth, mortality,cover and height of willows (Salix farriae, S. lutea, S. drummondiana and
S. exigua). S. lutea and S. exigua exhibited a lack of vitality, (i.e. vigor), as well as high mortality. Results were further complicated due to heavy browsing by elk which caused dwarfed, clubbed twigson S. lutea and S. exigua. All other wilow species exhibited thesame damage to a lesser degree. A significant correlation of sand content and willow growth and cover was reported (Patten
1968). Soils which supported willow stands were either sandy loamy (53-85% sand) or loamy sands (70-90% sand).
A study in southwestern New Mexico (Medina 1986) quantitatively examined riparian vegetation that had been greatly disturbed. Disturbance was attributed to anthropogenic factors of excessive past livestock grazing and upland deforestation. Medina (1986) concluded that this past disturbance manifested itself through substantial influences on stream morphology and riparian vegetation. The effect of past disturbance was substantiated through observation of changes in size class structure and species composition. 21
METHODS
Reconnaissance In the summer of 1986, a reconnaissance of all willow, cottonwood and aspen dominated communities of the
Crooked River National Grassland was conducted. These communities represented all types of riparian ecosystems ranging from hydric and mesic streamside communities to xeric upland seep/spring communities. A wide variety in community diversity, composition and structure within the study area was selected for detailed study in an attempt to include the widest range in the physical variablesover which the species occurred. Selection of study siteswas based on the presence of the Salicaceous dominants chosen for study. All study stands were located within riparian exclosures which had been established to exclude cattle. These exclosures ranged from 1 to 29 years old (Appendix A). Data were collected in a total of 125 stands which were dominated either by Salix lasiandra (n = 69), by S. lutea (n = 21), by S. lemmonii (n = 11), by Populus trichocarpa (n = 9), by P. tremuloides (n= 8) or by S. exigua (n = 7)(Appendix A). A stand of vegetation was delineated by the area falling under the canopy of the Salicaceous dominant. The canopy area could have included one to many individual plants depending on the Salicaceous species (i.e. S. lasiandra stands tended to exist as a single plant, whereas S. exigua stands tended to occuras a group of many stems). The sample numbers reflect the 22
relative abundance of each Salicaceous specieson the CRNG.
During initial reconnaissance, identification of the
overstory dominants (especially the willows), as wellas the understory species began. Often, collection of both male and female flowers of the Salix species was not possible until the following field season at which time they were collected for later identification. Taxonomy and nomenclature of the Salix species follows that of Brunsfield and Johnson (1985) and Kovalchik (1986), while that of the Carex and Juncus species follows that of
Kovalchik (1986). Taxonomy and nomenclature of the understory species follows that of Hitchcock and Cronquist
(1973). Appendix B lists the species encountered.
Vegetation
Salicaceous dominants were classified into three size classes (sapling, intermediate and decadent) based on diameter at 35 cm above the ground surface (Table 2). Size classes were selected based on natural breaks in the diameter for each species. A grand assumption that an increase in stem diameter reflects an increase in age, was made. Because these species are multi-stemmed, the largest stem of the largest individual within each stand was measured. The diameters within each size class varied 23
Table 2. Classification by diameter range and approximate age of the Salicaceae.
SAPLING
Species Diameter(cm) Approximate Age (yrs)
S.lasiandra .56 - 1.97 5- 10 S.lutea 1.33 - 2.15 4- 6 S.lemmonii .32 - 5.99 1- 9 P.tremuloides 1.33 - 4.38 3- 8 S.exiqua 2.06 - 2.74 3- 6
INTERMEDIATE
Species Diameter (cm) Approximate Age (yrs)
S.lasiandra 2.11 - 15.28 10- 15 S.lutea 3.08 - 6.62 6- 9 S.lemmonii 6.77 - 12.86 9- 17
DECADENT
Species Diameter (cm) Approximate Age (yrs)
S.lasiandra 20.37- 53.16 42- 46 S.lutea 13.82 29.29 18- 50 S.lemmonii 20.37- 23.87 20- 40 P.trichocarpa 25.40- 79.90 35- 66 P.tremuloides 7.80- 13.69 17- 42
S.exiqua 3.84- 9.72 10- 25 24
among the species due to differences in growth
characteristics (i.e. S. lasiandra tended to bean
arboreal species when large (old), whereas S. luteawere smaller, medium-sized shrubs (old)) (Table 2). The stands were aged by counting growth rings. The larger individuals were cored using an increment borer, while the smaller individualswere sacrificed (Table 2).
Average stand distance from the wetted channelwas measured in meters. This was defined as the distance of the center of the stand from the most adjacent freewater. Average riparian zone width, in meters, was measured for each stand. This zone was defined as the distanceover which riparian vegetation occurred, including thechannel if one was present. The age of the exclosures inyears
(grazing seasons) in which all stands occurredwas also recorded. 25
Water
Wetted channel width (the width of the free water surface) in meters and stream gradient (percent), at base
flow (August) were measured for each stand.
Soils
The following soil measurements were taken for each sampled stand.
Bulk density (g/cm3) was measured according to the core method as described in Black and Hartge (1986). A single core (approximately 5.0 cm in diameter by 3.5cm in height) was taken within the surface soil immediately below any organic horizon that may have existed. Thesame cores were used for the macroporosity determination.
Measurements of macroporosity in percent were accomplished through the use of a pressure chamber (OSU
Soil Physics Laboratory). The coreswere allowed to saturate over a 24 hour period and subsequently weighed.
The saturated cores were placed in a pressure chamber and allowed to equilibrate with 5.879 kPa of pressure. This standard pressure is equivalent to 60 cm of suction which is the tension at which water in pores >0.05mm in diameter (macropores) is vacated (Danielson and Sutherland
1986). Upon equilibration, the cores were removed from the chamber and weighed. Oven dry weight (24 hours at 100 0C) was obtained. Percent macropores was calculated using the 26
following formula:
MP = W(1) - W(2) x 100 x BD W(3)
MP = macropores, % by volume W(1) = saturated soil weight (g) W(2) = soil weight after equilibration with 5.879 kPa (g) W(3) = oven dry soil weight (g) BD = bulk density (g/cm3)
Depth to root restricting layers (i.e. impenetrable or gleyed horizons), were measured in meters utilizing a soil (wheatland) auger. If depths were greater thanone meter they were recorded as 1.01 m for data analysis purposes. Four estimates were taken within each stand.
To describe the influence of edaphic characteristics on species occupancy, percent organic matter, particle size analysis and percent coarse and fine materialswere measured. Composite samples from 5 selected locations within the stand were collected for analysis. The composite sample was composed of the upper 10 cm of the surface mineral horizon. Organic horizons (if present) were not included in the sample. Samples were placed in air-tight plastic bags until analyzed. Samples were air dried and mixed thoroughly prior to analysis.
The percent coarse materials (>2 mm diameter) and percent fine materials (< 2 mm diameter) were obtained by 27 dry sieving a known quantity of the air dry sample through a 2mm diameter sieve (Berg and Gardner 1978).
Determination of percent organic matter of the <2mm diameter fraction was accomplished utilizinga hydrogen peroxide (H202) digestion technique (Day 1965). This determination was done on 2 subsamples from each composite sample.
Particle size analysis was determined on an organic matter free sample. A modified Buoyoucos hydrometer method
(Gee and Bauer 1983) was used to determine soil textural class. Duplicate subsamples from each compositewere included. Textural classes were assigned according to the guidelines of the SCS (1975).
Soil pH (2:1 water:soil) was determined usinga glass electrode pH meter (Berg and Gardner 1978) on the <2mm diameter fraction of the soil sample. This determination was done on 2 subsamples from each composite sample.
Depth of an organic horizon, if present, in centimeters was measured at four locations within each stand. The four measurements were then averaged to get mean organic horizon depth.
Other Data
In addition to soils and physical location of the stand, other data were also collected to further characterize habitat including: 1) height and canopy cover of the dominant in meters, 2) width and length of the 28
stand in meters, 3) aspect in degrees and 4) elevation in meters.
Acronyms for the physical variables as theyoccur in subsequent tables can be found in Appendix C.
Data Analysis
To aid in the identification of the habitats occupied by the various Salicaceous species, the 19 environmental
(physical) variables were subjected to canonical discriminant analysis (CANDISC, SAS 1987). Discriminant analysis represents a multivariate approach to "pattern recognition and interpretation" (Williams 1983). The data input to discriminant analysis was composed of several individuals each having a grouping index (species) andan associated vector of measurements (physical variables).
The two major objectives of this type of analysisare 1) prediction and 2) separation (Williams 1983). Thepurpose of this discriminant analysis was for group separation of the Salix and Populus species based on an accompanying set of 19 environmental variables stratified according to size class (i.e. sapling, intermediate and decadent). This type of discriminant analysis "seeks to exhibit differences among populations by means of linear combinations of the observation variables which results in maximizingamong- group variation relative to within-group variation"
(Williams 1983). 29
The analytical process used for this data setwas to
1) use multivariate analysis of variance (MANOVA)to determine significant differenceamong groups, 2) classify each sample (vector of physical variable measurements for each stand) according to size class,
3) determine Mahalanobis' distances betweengroup (class) centroids and 4) display group separations in discriminant space (Pimentel 1979). 30
RESULTS Analysis of Salix and Populus Habitat Sapling Size Individuals
A very apparent attribute of the riparian stands dominated by Salicaceous plants at the CRNGwas the complete lack of newly establishing P. trichocarpa. Young cottonwoods from root suckering occurred across the study area, but nowhere were there "new" stands of young cottonwood. This may be a result of the loss of the habitat that this species requires (see discussion).
Within the sapling size class, means of all variables listed in Table 3 were tested for differences between species using an F test. There were significant differences between species for 6 variables (p < .15).
These variables were wetted channel width,average riparian zone width, average stand distance from the wetted channel, stream gradient, aspect and exclosureage. Average stand distance from the channel, stream gradient and aspect were significant at the p < .05 level. The differences associated with wetted channel width,average riparian zone width and exclosure age are heavily influenced by the presence of a lake (relatively large body of water) which has been exclosed for a relatively long period of time. When these three variables were removed from the analysis, the remaining three variables
(average stand distance from the wetted channel, stream gradient and aspect) were still highly significant (p < 31
Table 3. Means and test statistics (ANOVA) associated with physical variables of the sapling size class.
Sala Salu Sale Potr Saex Pr > F
N 16 8 4 4 4
pH 7.20 7.20 7.00 7.40 7.30 0.5201 MP (%) 23.63 29.21 27.78 32.34 28.12 0.3406 BD (g/cm3) 0.89 0.95 0.81 0.80 0.85 0.8082 CLAY (%) 20.20 22.00 24.17 16.15 22.70 0.6680 SAND (%) 56.08 52.94 47.82 67.10 50.75 0.6921 SILT (%) 23.81 25.16 28.08 16.85 26.68 0.8174 OM (%) 5.42 6.18 6.96 5.04 4.06 0.4814 COARSE (%) 34.51 29.63 23.63 19.40 41.69 0.2469 FINE (%) 65.49 70.37 76.37 80.60 58.31 0.2459 0 HORIZON (cm) 0.76 0.46 0.36 0.42 0.26 0.5936 IMPENETR (m) 0.50 0.45 0.74 0.68 0.52 0.7649 GLEYING (m) 0.73 0.81 >1.00 >1.00 >1.00 0.3700 WET CHAN (m) 36.14 138.09 1.06 0.46 274.13 0.1264* RIP ZONE (m) 15.00 42.33 8.72 5.21 78.71 0.1392* DIST FRO (m) 3.33 27.72 1.52 1.86 50.32 0.0432** GRADIENT (%) 9.00 8.00 20.00 19.00 4.00 0.0148** ASPECT (0) 169.00 90.00 248.00 225.00 11.00 0.0069** ELEVATION (m) 1066.00 1012.00 1114.00 1086.00 973.00 0.3611 EXCLOSURE (yrs) 10.00 13.00 10.00 7.00 20.00 0.1466*
* - physical variables with class means significantly different at the p < .15 level
** physical variables with class means significantly different at the p < .05 level
Multivariate Statistic F Pr > F
Wilks' Lambda 1.3244 0.1354 32
.05), with Pr > F values of .0432, .0148 and.0069 respectively. When the speciesgroups were tested by
MANOVA over all physical variables, Pr > F= .1354.
Differences in average stand distance fromthe channel for the sapling size members of the Salicaceae
were attributed to where the species occurred inresponse to fluctuation in water table depth. Specieswere ordered
from those which occur on flat valley bottomsup to those
that occur at the headwaters. The species occurredas
follows ranked from valley bottom to headwater:S. exigua (50.32m + 7.65m), S.lutea (27.72m + 6.80m), S. lasiandra
(3.38m + 3.36m), P. tremuloides (1.86m + 1.20m) and S.
lemmonii (1.52m + 1.01m) (Table 3). This phenomenonwas readily apparent in the field.
Stream gradient was another physical variable which
segregated species within the sapling size class. The variable is also related to the tendency for certain
species to occupy headwater stream systems, whileothers occurred on the flatter bottoms. S. lemmonii occupied
areas of steep stream gradient (20% + 3%), while P.
tremuloides also tended to occur in headwater systems(19% + 2%). S. lasiandra and S. lutea occupied streams of
similar gradient, 9% + 3% and 8% + 3%. The species which most obviously, (statistically and through observation),
occupied relatively flat streambeds was S. exigua (4%+
1%). 33
The two variables above, very accurately describe the positions of these species related to stream-valley geomorphology.
Aspect proved to be an interesting physical variable which the sapling size individuals "responded" to very strongly (Pr > F = .0069). S. exigua was found on streams with a generally northeast flow (11° + 5°), S. lutea on streams with an easterly direction (90° +_ 11°), S. lasiandra on streams with a southeasterly direction (169°
+ 100), with P. tremuloides and S. lemmonii on streams with a southwesterly flow (225° + 7° and 248° + 9° respectively). This attribute of these data is probably more indicative of the drainage direction (aspect) on the
CRNG than any vegetative response. The absence of the
Salicaceae of this size class on north- and northwest- facing slopes is readily apparent though, suggesting a possible need for higher soil temperatures as an establisment requirement for these species.
Of equal importance to these 'separating' variables are those which remain relatively constant for these species within this size class. These consistent variables include all soil-related variables (Table 3). Salicaceous species of the sapling size class occupied similar microsites of surface soil texture.
Canonical discriminant function analysis further substantiated the segregatory abilities of the above variables (Table 4). Canonical discriminant functions 34
Table 4. Summary of canonical discriminant function analysis of physical variables for the sapling size class.
CANONICAL DISCRIMINANT FUNCTIONS
PERCENT CUMULATIVE CANONICAL FUNCTION EIGENVALUE OF VARIANCE PERCENT CORRELATION
1 3.6923 0.5555 0.5555 0.8871 2 1.8502 0.2784 0.8338 0.8057 3 0.8072 0.1214 0.9553 0.6683 4 0.2973 0.0447 1.0000 0.4787
TOTAL CANONICAL STRUCTURE
VARIABLE FUNCTION 1 FUNCTION 2 FUNCTION 3 FUNCTION 4
PH 0.0831 0.1501 0.1427 0.5404 MP (%) 0.2342 0.3555 -0.0020 0.1685 BD (g/cm3) -0.1590 0.0330 -0.2502 0.0383 CLAY (X) -0.0385 0.0700 -0.1108 -0.5185 SAND (%) 0.0607 -0.0425 0.0995 0.5078 SILT (%) -0.0649 0.0210 -0.0770 -0.4236 OM (%) 0.1772 -0.0777 -0.3774 -0.2167 COARSE (%) -0.4092 -0.0193 0.1527 -0.2424 FINE (X) 0.4092 0.0193 -0.1527 0.2424 0 HORIZON (cm) -0.1343 -0.3006 -0.0803 0.1846 IMPENETR (m) 0.2359 -0.0371 0.1418 -0.1001 GLEYING (m) 0.2518 0.2506 0.2490 -0.1729 DIST FROM (m) -0.2517 0.5482 * 0.0751 -0.2770 GRADIENT (%) 0.6240 * -0.1465 0.0099 0.0534 ASPECT (o) 0.4803 -0.5098 * -0.0250 0.1711 ELEVATION (m) 0.2650 -0.3319 -0.0008 0.0370
* - highest r value 35
(CDFs) are linear combinations of those variables which best separate the species groups (S. lasiandra, S. lutea, S. lemmonii, P. trichocarpa, P. tremuloides and S. exiqua). Canonical discriminant function analysiswas run on each size class within each species group. The eigenvalue, percent variance, cumulative percent variance and canonical correlation related to each canonical discriminant function are indications of that function's dicriminatory power (Noon 1981). CDF 1 and CDF 2 explained 83.38% of the variation in species groups. The values of total canonical structure (Table 4) are the correlations between 16 of the original 19 physical variables (three were omitted to remove the overpowering influence of the lake) and the computer generated canonical discriminant functions.
A graph of the sapling sized individuals displayed in canonical discriminant space exhibits these individuals grouped by species (Figure 3). P. tremuloides and S. lemmonii are very different in their habitat according to stream-valley geomorphology than are the remaining three species. Further substantiation for the existence of these groups in discriminant space are the Mahalanobis' distances between group centroids (Table 5). P. tremuloides and S. lemmonii are very similar (distance of
6.5968) while at the other extreme, these two are very dissimilar with S. exiqua (distance of 37.5591 and 27.9585 respectively). The discriminant analysis indicated that 36
3 IIIIIIIIIIIIIIIIITIIIIIIIIIIIII1IIIIIIII -3 -2 -1 0 1 2 3 4 , 5
CDF 1
Figure 3. Plot of Canonical Discriminant Functions 1 and 2 for Sapling Size Individuals. Symbols: (A) S. lasiandra; (B) S. lutea; (C) S. lemmonii; (E) P. tremuloides; (F) S. exigua. 37
Table 5. Mahalanobis, distances between group centroids for the sapling size class.
Squared Distance To
Distance From Sala Salu Sale Potr Saex
Sala 0
Salu 8.7622 0
Sale 21.4594 21.1903 0
Potr 20.8338 17.3658 6.5968 0
Saex 13.4922 10.5853 37.5591 27.9585 0 38
CDF 1 was most highly correlated with increasingstream gradient (r = .6240) while CDF 2was most correlated to
increasing distance from the stream channel(r = .5482)
and a decreasing response to aspect (r= -.5098) (Table
4). Relative to these two variables, the Salix andPopulus species occupied different locations along these gradients.
Along an environmental gradient of increasing stream
gradient (i.e. an elevational gradient from downstreamup
to headwater stands), the species occurredas follows: S.
exigua, S. lasiandra, S. lutea, P. tremuloidesand S. lemmonii (Figure 3).
Along the secondary gradient of increasingaverage stand distance from the wetted channel, the species
occurred as follows: S. lasiandra, S. lemmonii, P.
tremuloides, S. lutea and S. exigua (Figure 3).
Intermediate Size Individuals
This data set consisted of only three of the six species studied: S. lasiandra, S.lutea and S.lemmonii.
There were no other species of this size class at the CRNG
(Table 2). Hypothetically, during the time frame when
these individuals of the intermediate size class were
establishing, the exclosures did not exist. As a result those species that were apparently more sensitive to past
cattle use (P. trichocarpa, P. tremuloides and S. exigua) 39
did not establish during this time periodand are conspicuously absent from the current population.
The intermediate size class of Salix species
exhibited significant differences in the following
physical variables at the p < .15 level: soil
macroporosity, soil organic matter content anddepth to an impenetrable layer (Table 6). Of these three variables,
soil macroporosity and soil organic mattercontent were significant at the p < .05 level (MANOVA of all physical
variables, Pr > F = .0095). These significantedaphic
variables suggest that the Salix species of thissize class vary in their habitats according to soil structure.
Soil macroporosity and soil organic matter contentof the surface soil are indicative of the moisture retention ability of the soil. Depth to an impenetrable layer is
also indicative of moisture retention, but ata deeper level in the soil. If an impermeable layer is present in
the soil profile, water tends to pondupon this layer creating a perched water table. Riparian plant species vary in their abilities to exist in this type of soil condition.
Differences in soil macroporosity for this size class is interpreted as one of an increasing need for unbound water (i.e. water available for plant growth and maintenance). The species occurred as follows, ranked according to increasingly macroporous surface soils: S. lutea (25.30% + 2.50%), S. lasiandra (27.00% + 1.61%) and 40
Table 6. Means and test statistics (ANOVA) associated with physical variables of the intermediate size class.
Sala Salu Sale Pr > F
N 30 9 3
pH 7.40 7.30 7.10 0.5739 MP (%) 27.00 25.30 44.80 0.0039** BD (g/cm3) 0.87 0.95 0.71 0.2877 CLAY (%) 25.62 22.61 22.00 0.5414 SAND (%) 48.13 53.91 53.43 0.6853 SILT (%) 26.32 23.54 24.60 0.8651 OM (%) 5.54 7.54 11.41 0.0131** COARSE (%) 27.77 36.93 36.07 0.2903 FINE (%) 72.22 63.01 63.93 0.2873 0 HORIZON (cm) 0.62 0.41 0.37 0.7378 IMPENETR (m) 0.54 0.24 0.38 0.0681* GLEYING (m) 0.87 0.81 0.77 0.7873 WET CHAN (m) 75.47 61.63 1.40 0.7951 RIP ZONE (m) 29.94 20.34 10.21 0.7620 DIST FROM (m) 10.83 14.05 5.88 0.9061 GRADIENT (%) 8.00 8.00 15.00 0.1575 ASPECT (o) 130.00 90.00 195.00 0.2747 ELEVATION (m) 1019.00 1053.00 1128.00 0.2309 EXCLOSURE (yrs) 11.00 11.00 8.00 0.7200
* physical variables with class means significantly different at the p < .15 level
** physical variables with class means significantly different at the p < .05 level
Multivariate Statistic F Pr > F
Wilks' Lambda 2.1158 .0095 41
S. lemmonii (44.80% + 4.58%). Depth toa gleyed horizon also supports this observation. A gleyed horizon
(indicative of water table depth)was closest to the soil surface for S. lemmonii and deepest for S. lutea.
Percent soil organic matter content was another
physical variable which readily segregated the
intermediate sized individuals. This variablewas
indicative of the relative degree to which theleaves of
these species decayed. In other words, the leavesof these species appeared to contain varying amounts of
recalcitrant materials. This phenomenon of increasingsoil organic matter content was interpreted to also be
indicative of the relationship to surface soil structure.
The species were ordered as follows: S. lasiandra (5.54%+
1.62%), S. lutea (7.54% + 1.83%) and S. lemmonii (11.41%+
2.94%).
Depth to an impenetrable layer was a physical
variable which influenced these species. This gradientwas interpreted to indicate species response to water table
depth. S. lutea occupied areas where the water tablewas close to the surface (.24m + .55m), S. lemmonii at deeper
water tables (.38m + .65m), with S. lasiandra occurring in
areas of the deepest water tables (.54m + .58m)(Table 6). As was apparent in the sapling size class, the soil-
related variables (except for the three above) did not vary within this size class between all species (Table 6).
Salicaceous species of the intermediate size class 42 occupied similar microsites based on most of the surface soil characteristics.
Canonical discriminant function analysis further supported these observations of the separating powers of the above variables (Table 7). CDF 1 and CDF 2 explained
100% of the variation (the maximum number of CDFs is equal to the number of classes minus one: 3 classes minus 1 equals 2 CDFs) in species groups (Figure 4).
Further substantiation for the existence of these groups in discriminant space are the Mahalanobis' distances between group centroids (Table 8). S. lasiandra and S. lutea were very similar with a distance of 5.6318, while S. lemmonii was very dissimilar from them with distance values of 27.2597 and 25.6197. The analysis indicated that CDF 1 was most highly correlated with increasing soil macroporosity (r = .5590) and increasing soil organic matter content (r = .5334), while CDF 2 was most highly correlated to depth to an impenetrable layer (r = .4651) (Table 7). CDF 1 was interpreted to be an environmental gradient in response to soil structure (surface soil moisture retention capacity) and CDF 2, an environmental gradient due to depth to water table.
Overall, areas closest to the stream origin are driest, while those areas farther away from the origin are wettest. 43
Table 7. Summary of canonical discriminant function analysis of physical variables for the intermediate size class.
CANONICAL DISCRIMINANT FUNCTIONS
PERCENT CUMULATIVE . CANONICAL FUNCTION EIGENVALUE OF VARIANCE PERCENT CORRELATION
1 1.9236 0.6753 0.6753 0.8521 2 0.9248 0.3247 1.0000 0.7551
TOTAL CANONICAL STRUCTURE
VARIABLE FUNCTION 1 FUNCTION 2
pH -0.2056 0.0229 MP (%) 0.5590 * 0.2948 BD (g/cm3) -0.1996 -0.2725 CLAY (%) -0.1601 0.1713 SAND (%) 0.1085 -0.1544 SILT (%) -0.0526 0.1078 OM (%) 0.5334 * -0.1590 COARSE (%) 0.1926 -0.2777 FINE (%) -0.1927 0.2794 0 HORIZON (cm) -0.1125 0.1219 IMPENETR (m) -0.1941 0.4651 * GLEYING (M) -0.1146 0.0860 DIST FROM (m) -0.0469 -0.0865 GRADIENT (%) 0.3522 0.1355 ASPECT (C) 0.1771 0.3055 ELEVATION (m) 0.3248 -0.0791
* highest r value 44
imitiiiiiiiiiiiriiiiitilitiiiiiiiiitilif it' -3 -2 -1 0 1 2 3 4 5 6 CDF 1
Figure 4. Plot of Canonical DiscriminantFunctions 1 and 2 for Intermediate Size Individuals.Symbols:(A) S. lasiandra; (B) S. lutea;(C) S. lemmonii. 45
Table 8. Mahalanobis' distances between group centroids for the intermediate size class.
Squared Distance To
Distance From Sala Salu Sale
Sala 0
Salu 5.6318 0
Sale 27.2597 25.6197 0 46
Along the gradient of increasing surface moisture retention, the species occured as follows: S. lasiandra,
S. lutea and S. lemmonii (Figure 4).
Along the gradient of response to water table depth, the species occurred as follows: S. lutea, S. lasiandra and S. lemmonii (Figure 4).
Decadent Individuals All the Salicaceous species were present in this class. The individuals of this size class ranged over various stages of complete overstory dominance to extreme deterioration. The most noticeable of these, was P. trichocarpa. All of the cottonwoods of this size class across the CRNG were very decadent with a high proportion of dead crowns in all the individuals. The physical variables associated with the decadent individuals were tested for differences in habitat (Table
9). Depth to an impenetrable layer was significant at the p < .15 level, while seven additional variables were significant at the p < .01 level. These were soil macroporosity, wetted channel width, average riparian zone width, average stand distance from the wetted channel, stream gradient, elevation and exclosure age.
As occurred in the sapling size data, the differences associated with wetted channel width, average riparian zone width and exclosure age, were heavily influenced by the presence of the lake which had been exclosed to 47
Table 9. Means and test statistics (ANOVA) associated with physical variables of the decadent size class.
Sala Salu Sale Potr1 Potr Saex Pr > F
N 22 4 4 9 4 4
pH 7.40 7.20 7.00 7.50 7.20 7.40 0.5152 MP (%) 23.89 25.30 28.74 28.63 39.82 22.31 0.0003* * BD (g/cm3) 0.96 1.05 0.99 0.92 0.77 0.98 0.5631 CLAY (%) 21.14 20.32 16.98 19.84 16.32 12.42 0.5262 SAND (%) 55.86 54.40 49.32 50.61 56.58 69.85 0.6332 SILT (%) 23.08 25.35 33.78 29.56 22.15 17.78 0.4981 OM (%) 5.75 12.57 5.18 4.83 5.17 3.47 0.1522 COARSE (%) 29.81 30.86 21.70 19.37 10.42 21.69 0.1957 FINE (%) 70.18 69.14 78.30 80.63 89.58 78.31 0.1957 0 HORIZON (cm) 0.61 0.52 1.04 0.39 0.52 0.86 0.8164 IMPENETR (m) 0.60 0.32 >1.00 0.72 0.94 0.68 0.1002* GLEYING (m) 0.98 >1.00 >1.00 0.91 >1.00 0.80 0.5044 WET CHAN (m) 27.80 1.04 547.62 62.48 0.88 410.93 0.0001** RIP ZONE (m) 17.93 8.52 163.83 37.12 11.53 58.88 0.0001** DIST FROM (m) 4.50 0.75 76.58 17.29 7.79 22.14 0.0001** GRADIENT (%) 10.00 7.00 3.00 5.00 19.00 4.00 0.0043** ASPECT (0) 147.00 79.00 90.00 125.00 112.00 214.00 0.6474 ELEVATION (m) 1053.00 1141.00 866.00 915.00 1083.00 928.00 0.0021** EXCLOSURE 7.54 5.5 29.00 12.89 8.25 24.25 0.0001**
* - physical variables with class means significantly different at the p < .15 level
** physical variables with class means significantly different at the p < .05 level
Potr1 quaking aspen
Potr black cottonwood
Multivariate Statistic F Pr > F
Wilks' Lambda 2.1118 0.0001 48 livestock grazing for a disproportionate period of time relative to the other exclosures. When these three variables were removed from the analysis, the remaining five variables (depth to an impenetrable layer, soil macroporosity, average stand distance from the wetted channel, stream gradient and elevation) remained highly significant. Depth to an impenetrable layer was significant at p < .15 (Pr > F = .1002), while the other variables, soil macroporosity, average stand distance to the wetted channel, stream gradient and elevation were significant at p < .01, Pr > F of .0003, .0001, 0043 and .0021 respectively. When the species groups were tested by MANOVA over all physical variables, Pr > F = .0001.
Differences in soil macroporosity for the decandent sized individuals are due to the occurrence of these species over an environmental gradient interpreted as one of an increasing need for unbound water, or oxygenation. This gradient was suggested for intermediate sized individuals as well. The species occurred as follows ranked according to this variable: S. exiqua (22.31% +
1.66%), S. lasiandra (23.89% + 2.39%), S. lutea (25.30% +
2.78%), P. trichocarpa (28.63% + 2.42%), S. lemmonii
(28.74% + 2.27%) and P. tremuloides (39.82% + 2.43%)
(Table 9). The appearance of soil macroporosity as a separator of species groups in both the intermediate and decadent size classes, alludes to the relationship of the species to surface soil structure. The occurrence of S. 49 lemmonii and P. tremuloides on very sandy microsites was readily observed in the field over all size classes, but especially when decadent. As time progresses, these species seem to occupy areas of increasingly porous soils.
Depth to an impenetrable layer was a physical variable which influenced these species both in the intermediate and the decadent size classes. This was again
interpreted to be an indication of the degree to which the species could tolerate a deep water table. The species ranged from S. lutea (.32m + .62m) being the least tolerant, to S. lasiandra (.60m + .62m), S. exiqua (.68m +
.62m), P. trichocarpa (.72m + .63m), P. tremuloides (.72m
+ .39m) with S. lemmonii (>1.00m) being the most tolerant.
Differences in average stand distance from the channel for the decadent size class occurred. This variable is a function of valley bottom width, (i.e.
restricted versus unrestricted stream systems). The
species occurred as follows, ranked from most to least
restricted stream channels: S. lutea (.75m + .54m), S. lasiandra (4.50m + 3.92m), P. tremuloides (7.79m + 3.55m),
P. trichocarpa (17.29m + 5.34m), S. exiqua (22.14m + 5.61m), and S. lemmonii (76.58m + 4.05m) (Table 9).
Not surprising was the fact that stream gradient
readily segregated the decandent size individuals as it
did for the saplings. This variable accounted for the
tendency of certain species to occupy headwater (low
order) stream systems, while others occurred on the 50 flatter (higher order) bottoms. The species occurred as follows, from headwater (restricted) to downstream (unrestricted) systems: P. tremuloides (19% + 2%), S. lasiandra (10% + 3%), S. lutea (7% + 1%), P. trichocarpa
(5% + 2%), S. exigua (4% + 1%) and S. lemmonii (3%)(Table
9). The most significant aspect of this ranking is the presence of P. tremuloides in the steeper, headwater drainages of the CRNG. This same pattern was evident for the sapling size class. The decadent sized individuals responded to an increase in elevation. They were ordered as follows from highest to lowest: S. lutea (1141m + 4m), P. tremuloides
(1083m + 7m), S. lasiandra (1053m + 12m), S. exigua (928m
_+ 11m), P. trichocarpa (915m + 11m) and S. lemmonii (866m) (Table 9). This relationship was apparent from field observations, and represented sampling error rather than any real ecologcial phenomenon. As was apparent in the younger size classes the soil- related variables (except for macroporosity) were not different among species (Table 9). Decadent sized Salicaceous species occupied similar microsites based on the majority of surface soil characteristics. Canonical discriminant function analysis further substantiated the separating powers of the above variables
(Table 10). CDF 1 and CDF 2 explained 81.63% of the variation in species groups. Further substantiation for the existence of these groups in discriminant space are 51
Table 10. Summary of canonical discriminant function analysis of physical variables for the decadent size class.
CANONICAL DISCRIMINANT FUNCTIONS
PERCENT CUMULATIVE CANONICAL FUNCTION EIGENVALUE OF VARIANCE PERCENT CORRELATION
1 2.9809 0.4368 0.4368 0.8653 2 2.5900 0.3795 0.8163 0.8494 3 0.5684 0.0833 0.8996 0.6020 4 0.4230 0.0620 0.9615 0.5452 5 0.2625 0.0385 1.0000 0.4560
TOTAL CANONICAL STRUCTURE
VARIABLE FUNCTION 1 FUNCTION 2 FUNCTION 3 FUNCTION 4
pH -0.1421 0.0990 -0.4054 -0.1850 MP (%) 0.7394 * -0.0324 -0.0889 -0.0006 BD (g/cm3) -0.2715 -0.0208 0.2924 -0.0642 CLAY (%) -0.0489 0.1984 -0.0755 -0.2230 SAND (%) -0.1460 0.0280 -0.1835 0.2679 SILT (%) 0.1282 -0.1943 0.2390 -0.2834 OM (%) -0.0292 0.2800 0.5112 -0.1973 COARSE (%) -0.3511 0.1991 0.2207 0.0326 FINE (X) 0.3511 -0.1991 -0.2207 -0.0326 0 HORIZON (cm) -0.0634 -0.1393 0.1313 0.3064 IMPENETR (m) 0.3292 -0.3460 -0.1230 0.2485 GLEYING (m) 0.1407 0.1819 0.2867 0.1201 DIST FROM (m) 0.1620 -0.7609 * 0.4787 0.2602 GRADIENT (%) 0.3849 0.4679 * -0.2524 0.3626 ASPECT (0) -0.1876 -0.0305 -0.3270 0.1692 ELEVATION (m) -0.0069 0.6826 * 0.1514 0.2042
* highest r value 52 the Mahalanobis' distances between group centroids (Table
11). P. tremuloides and S. exigua are extremely dissimilar with a distance value of 55.4772. This is due to the fact that neither occur in the others habitat - P. tremuloides is a headwater species, while S. exigua is a bottom land
species. S. lasiandra and S. lutea occupy very similar
sites with a distance value of 6.4995. The discriminant
analysis indicated that CDF 1 was most highly correlated with increasing soil macroporosity (r = .7394) while CDF 2 was most highly correlated to decreasing stand distance from the wetted channel (r = -.7609), increasing elevation
(r = .6826) and increasing stream gradient (r = .4679)
(Figure 5). CDF 1 was interpreted to represent a gradient
of aggrading soil structure, in particular moisture retention ability, while CDF 2 was interpreted to be a
gradient of headwater to basin riparian systems. Along the gradient of headwater to basin ecosystems,
the species occurred as follows: S. exigua, S. lasiandra, S. lutea, P. trichocarpa, S. lemmonii, and P. tremuloides
(Figure 5). Along the gradient of decreasing stand distance from
the wetted channel, the species occurred as follows: S.
lemmonii, S. exigua, P. trichocarpa, S. lasiandra, P.
tremuloides and S. lutea (Figure 5). 53
Table 11. Mahalanobis, distances between group centroids for the decadent size class.
Squared Distance To
Distance From Sala Salu Sale Potr1 Potr Saex
Sala 0
Salu 6.4995 0
Sale 23.1080 34.4843 0
Potr1 7.3718 16.3529 11.4553 0
Potr 27.9691 31.1580 36.0205 23.0148 0
Saex 11.9906 25.5534 20.6684 13.5169 55.4772 0 54
4- 3- 2-
1
N0- LL_ C: 1 CD -2-_ -3- -4-
-5 1 IIIIIIIIIIIIIIIIIIIIIII1 -4 -2 0 2 4 6
CDF 1
Figure 5. Plot of Canonical Discriminant Functions1 and 2 for Decadent Size Individuals. Symbols; (A) S. lasiandra; (B) S. lutea;(C) S. lemmonii; (D) P. trichocarpa; (E) P. tremuloides; (F) S. exigua. 55
DISCUSSION Population Structure Under-representation of a size class (usually the smaller ones) may be due to the absence of regeneration,
infrequent reproductive events and/or high sapling
mortality (Harcombe and Marks 1978). The estimatedpre- exclusion population of the Salicaceous species at the CRNG is represented in Figure 6a. The pre-exclusion
population structure was estimated by subtracting out
those individuals which were younger than theage of the exclosure in which they occurred. From stem-age analysis,
it is safe to assume that the individuals< 8cm in
diameter were less than about nine years inage and were therefore extremely scarce. Prior to exclusion, the
majority of these smaller individuals did not exist in the population. Given the preponderance of the Salicaceae since exclusion and their absence outside the exclosures,
abusive grazing management practices prior to exclusion probably limited its abundance. The cattle most likely grazed any year-old seedlings that may have escaped the previous grazing season. Logic dictates that the
implementation of corridor fencing (cattle exclusion) began none too soon. Without the implementation of corridor fencing, it is probable that the Salicaceae would soon disappear from the landscape.
The current population structure of the Salicaceous species, as a whole, of the Crooked River National 56
<2 5 6 7 8 9 20 30 30+ Diameter class (cm)
Figure 6a. Diameter class distribution of the Salicaceae present prior to exclosure construction (n=65).
3 5 6 7 8 9 20 30 30+ Diameter class (cm)
Figure 6b. Current diameter class distribution of the Salicaceae in exclosures (n=125). 57
Grassland shows the presence of both sapling and decadent stands with a depauperate number of intermediate sized stands (Figure 6b). The population represented in this figure has been protected from livestock grazing through the use of exclosures from 1 to 29 years old (Appendix A). Hypothetically, this is attributed to the abusive grazing practices of the past which prevented the establishment of these species. The past grazing pressure, in effect, inhibited regeneration of the Salicaceae. With the implementation of corridor fencing, individuals established and survived in an environment protected from grazing. Since exclusion, juveniles have become a substantial portion of the population. This will facilitate eventual replacement of the larger, decadent stands which is necessary for the perpetuation of Salicaceae stands and their associated values on the CRNG.
The current population structure of P. trichocarpa suggests that certain habitat requirements are still not being met for its recovery on the CRNG (Figure 7). Regardless of corridor fencing, there were no new, establishing stands of black cottonwood at the CRNG. This is attributed to the loss of the species' requirements for establishment on new sites.
In an eastern Oregon riparian area, P. trichocarpa was found to germinate and establish exclusively on young
(point) gravel bars (Kauffman et al. 1985). As a result of alterations in channel physiognomy and runoff patterns, 58
10 9- 8- r0 7- 14*.. 11 .6. 6- 01 5- 001 4- .'44 ..4 3- 144 14. 2- 01:
11 0 , , . (2 3 4 5 6 7 8 9 20 30 30+
Diameter class (cm)
Figure 7. Diameter class distribution of Populus trichocarpa. 59
there was no evidence that point barswere occurring on
the CRNG, which substantiates the lack of habitatfor
germination and establishment. Until the creeksand
riparian areas reach a new equilibrium where pointbars are created, cottonwood establishment will be limited to chance microsites.
In a study of P. deltoides var. occidentalis Rydb.
(plains cottonwood), the best conditions for seedling recruitment were found to occur on periodically flooded
point bars where rapid sedimentation and lateral migration took place (i.e. highly fluvially-disturbed environments)
(Bradley and Smith 1986). These conditions occurredon an average of one in five years on a river in Alberta,
Canada. Assuming that the establishment requirementsare
similar for P. trichocarpa at the CRNG, thesequence of
events necessary to create germination sites have notcome to pass for some time. Because of channel downcutting, the
floodplains are, in effect, cut off from their aquatic systems and as such are no longer a functional part of the
riparian ecosystem. Sediment deposition, and therefore establishment sites for P. trichocarpa is no longer occurring.
The ecological significance of the above is that there is high potential for the local extinction of this species on the CRNG. Through exclosures, P. trichocarpa stands may at least remain as relict sites at their present population status. 60
Currently at the CRNG, the primarymeans of reproduction for both of the Populusspp. was though root suckering. This reproductive strategy led toan increase in size/cover of the existing stands,but no establishment
of new stands was found. No observation of seedlingswas made for the Populus specieson the first to third order tributaries.
The Salix species of this area also tendedto reproduce vegetatively. This was accomplishedwhen at higher stream flows, branches and twigswere broken off, carried downstream and subsequently deposited into
alluvial materials. Onlyone observation of a young S.
lasiandra that germinated from seedwas made.
Habitat Changes Through Time
An interesting result of this researchwas the similarity in surface soil characteristicsamong all of
the Salicaeous species. The physical variablesof soil texture, (i.e. percent sand, silt and clay, andpercent
fine and coarse materials) were consistent (Tables12-15).
These species require sandy-textured soils (47.87%to
69.85% sand) in order to establish and survive. Whenthe consistency in the variable of soil macroporosity is coupled with those of high sand content and high percent coarse materials, the inference that these species require high amounts of unbound water and surface soil aeration can be drawn. Bulk density was relatively consistent for 61
all species and stands (approximately .89 g/cm3).The soil pH remained consistent for these speciesover time, at an
approximately normal level of 7.3. Intuitively, thismakes
sense since these soils are all effected by thesame
chemical processes. In other words, the pH of therainfall and snowmelt, of the allochthonous materials thatmay wash onto the banks, of the soil parent materials,or of other processes that may effect the soil pH, are probably
relatively consistent throughout the entire studyarea. In all of the other physical variables measured, the
species occupied various habitats from sapling todecadent sized stands.
Salix lasiandra
S. lasiandra was the most common willow occupying the CRNG. It also exhibited the broadest ecological amplitude
of all the species examined. Given its broad ecological
amplitude, it should generally be the species of choicein any transplanting endeavor in this geographic area.
Only one variable was significantly different when tested between age classes (Table 12). The physical variable which did vary slightly wasaverage stand distance from the wetted channel. Sapling and decadent
sized individuals occurred somewhat closer to thechannel than did intermediate sized individuals. Thiswas interpreted to be due to change in the channel and 62
Table 12. Means of the physical variables associated with SALIX LASIANDRA.
variable SAPLING INTERMEDIATE DECADENT (n = 16) (n = 30) (n = 22)
pH 7.20 a 7.40 a 7.40 a MP (%) 23.63 a 27.00 a 23.89 a BD (g/cm3) 0.89 a 0.87 a 0.96 a CLAY (%) 20.20 a 25.62 b 21.14 a SAND (%) 56.08 a 48.13 a 55.86 a SILT (%) 23.81 a 26.32 a 23.08 a OM (%) 5.42 a 5.54 a 5.75 a COARSE (%) 34.51 a 27.77 a 29.81 a FINE (%) 65.49 a 72.22 a 70.18 a 0 HORIZON (cm) 0.76 a 0.62 a 0.61 a IMPENETR (m) 0.50 a 0.54 a 0.60 a GLEYING (m) 0.73 a 0.87 ab 0.98 b DIST FROM (m) 3.33 a 10.83 b 4.50 a GRADIENT (X) 9.00 a 8.00 a 10.00 a ASPECT (D) 169.00 a 130.00 a 147.00 a ELEVATION (m) 1066.00 a 1019.00 a 1053.00 a
no significant difference between values with a letter in common (Mann-Whitney test) 63
floodplain physiognomy at the time these intermediate
sized individuals established, (i.e. stream meandering).
Statisically, depth to gleying was significantly different between age classes, attributable to sampling
error only.
Salix lutea Percent surface soil organic matter content
increased over the age classes for S. lutea (Table 13).
The amount remained consistent from sapling sized individuals to intermediate sized individuals, but then
increased from intermediate to decadent individuals. This was attributed to an increase in litter deposition by these stands as they mature. The enhanced organic carbon content no doubt resulted in an altered soil physical
environment. The physical variable of average stand distance from
the wetted channel changed between age classes (Table 13).
As S. lutea matured, they occupied areas increasingly close to the wetted channel. This response could be due to
a variety of events. Since establishment, the stream physiognomy (structure) could have been altered. This
response could have been due to the influence of the
larger and larger willows on the stream channel. This
species tends to be a medium-sized, multi-stemmed shrub at
maturity. The growth form of S. lutea as it matures is
more of a lateral than vertical spread. Many times 64
Table 13. Means of the physical variables associated with SALIX LUTEA.
variable SAPLING INTERMEDIATE DECADENT (n = 8) (n = 9) (n = 4)
pH 7.20 a 7.30 a 7.20 a MP (%) 29.21 a 25.30 a 25.30 a BD (g/cm3) 0.95 a 0.95 a 1.05 a CLAY (X) 22.00 a 22.61 a 20.32 a SAND (X) 52.94 a 53.91 a 54.40 a SILT (%) 25.16 a 23.54 a 25.35 a OM (%) 6.18 a 7.54 a 12.57 b COARSE (%) 29.63 a 36.93 b 30.86 a FINE (%) 70.37 a 63.01 b 69.14 a OHORIZON (cm) 0.46 a 0.41 a 0.52 a IMPENETR (m) 0.45 a 0.24 a 0.32 a GLEYING (m) 0.81 a 0.81 a >1.00 b DIST FROM (m) 27.72 a 14.05 b 0.75 c GRADIENT (%) 8.00 a 8.00 a 7.00 a ASPECT (0) 90.00 a 90.00 a 79.00 a ELEVATION (m) 1012.00 a 1053.00 a 1141.00 b
no significant difference between values with a letter in common (Mann-Whitney test). 65
individuals can extendover the entire stream channel.
These willows are retaining organic and inorganicalluvium resulting in a deepening and narrowingof channel physiognomy.
Populus tremuloides
More than the previously mentioned species,P.
tremuloides has very specific habitat requirementsof surface soil characteristics (Table 14)on the CRNG. This
could be due to the high moisture requirementsof this
species. The semi-arid environment of the CRNG isat the extreme end of aspen's tolerance. It is likely that its
existence at the CRNG is restricted toareas of sandy-steep springs, seeps and first order tributaries
only.
The most powerful variable which separated P.
tremuloides habitat from all otherswas stream gradient (Table 14). This species was restricted to headwater tributaries and springs only. Habitat requirementsof this species are provided only in headwater type riparian ecosystems at the CRNG. Consequently, theseare the only areas where propagation, either by natural processes or transplanting should be attempted.
As P. tremuloides matured, it occurred fartheraway from the wetted channel (Table 14). As for the other three
Salix species, this was attributed to change inchannel 66
Table 14. Means of the physical variables associated with POPULUS TREMULOIDES.
variable SAPLING INTERMEDIATE DECADENT (n = 4) (n = 0) (n = 4)
pH 7.40 a 7.20 a MP (%) 32.34 a 39.82 a BD (g/cm3) 0.80 a 0.77 a CLAY (%) 16.15 a 16.32 a SAND (%) 67.10 a 56.58 a SILT (%) 16.85 a 22.15 a OM (%) 5.04 a 5.17 a COARSE (%) 19.40 a 10.42 a FINE (%) 80.60 a 89.58 a 0 HORIZON (cm) 0.42 a 0.52 a IMPENETR (m) 0.68 a 0.94 a GLEYING (m) >1.00 a >1.00 a DIST FROM (m) 1.86 a 7.79 b GRADIENT (%) 19.00 a 19.00 a ASPECT (0) 225.00 a 113.00 b ELEVATION (m) 1086.00 a 1083.00 a
no significant differnce between values with a letter in common (Mann-Whitney test). 67 physiognomy during the establishment periods between the sapling sized and decadent sized stands.
Salix exiqua S. exigua was the only species in which depth of the organic horizon was significant from sapling to decadent stands (Table 15). Along the successional gradient from sapling-dominated to decadent stands, the organic horizon became increasingly deeper. As with S. lutea, this was attributed to the greater amounts of leaf litter deposition onto the soil surface of the decadent sized
stands. S. exigua exhibited change in average stand distance from the wetted channel over time (Table 15). This species
is increasingly closer to the wetted channel for sapling- dominated stands than decadent stands. Again, this is
attributed to channel meandering. This is also indicative
of the growth pattern of S. exigua. The pattern of stand expansion is such that stands of S. exigua are structurally diverse (i.e. there are often at least three
obvious strata in any single stand). The tallest stratum
occurs the closest to the wetted channelwhile the
shortest occurs the farthest fromthe wetted channel.
This could be in response to a moisture gradient. This
pattern was readily repeatable across the CRNG. S. exiqua was found only in areas of very flat stream
gradient (Table 15). These are the only areas where 68
Table 15. Means of the physical variables associated with SALIX EXIGUA.
variable SAPLING INTERMEDIATE DECADENT (n = 4) (n = 0) (n = 4)
pH 7.30 a 7.40 a MP (%) 28.12 a 22.31 b BD (g/cm3) 0.85 a 0.98 a CLAY (%) 22.70 a 12.42 b SAND (%) 50.75 a 69.85 a SILT (X) 26.68 a 17.78 a OM (X) 4.06 a 3.47 a COARSE (%) 41.69 a 21.69 b FINE (X) 58.31 a 78.31 b 0 HORIZON (cm) 0.26 a 0.86 b IMPENETR (m) 0.52 a 0.68 b GLEYING (m) >1.00 a 0.80 a DIST FROM (m) 50.32 a 22.14 b GRADIENT (%) 4.00 a 3.50 a ASPECT (0) 11.00 a 214.00 b ELEVATION (m) 973.00 a 927.00 b
no significant difference between values with a letter in common (Mann-Whitney test). 69
propagation of this species, either by naturalprocesses or by transplanting should be focused.
Management Implications
An important overall finding of this research is the remarkable response of the Salicaceae to protection of their habitat from livestock grazing. This study indicates
that the Salicaceae, especially of the smaller size class,
require areas in which the natural processes thatgovern the creation of their specific habitats (germination and
establishment sites) are allowed to take place. At the
Crooked River National Grassland, the only proven method of attaining these habitats through time is by the
exclusion of livestock grazing. However,numerous benefits occur due to this management scheme. One such benefit is the provision of clean, potable, easily accessible water
for livestock which is pumped from the riparian zone to
troughs, supplied through the entire year. Many times ifa water supply system does not exist in some pasture, water gaps are left in the riparian fences, for cattle to use. Implications of riparian rehabilitation through willow transplanting arise from this research project. For moderately successful results over the largest number of riparian areas, S. lasiandra cuttings are recommended.
This is due to the broad ecological amplitude of this
species of all the species examined. The largest of the sapling sized (Table 2) material should be used. Material 70
of this size is often large enough to survivethe cutting process, and small enough to bend during accelerated
stream flows. Proper transplanting procedure would include
cutting the saplings one day prior to planting,and
soaking them overnight in Root-Tone (F.Russell, personal communication). It is important to plant the cuttings
immediately prior to bud burst, preferrably duringthe
spring when stream flow is sufficiently low toallow estimation of the base flow. Surface soil characteristics should be as follows:
1. pH from 6.6 to 7.8
2. soil macroporosity from 11.55% to 41.09%
3. sand content from 29.10% to 82.20%
4. coarse materials from 5.95% to 75.28%
5. soil organic matter content from 1.98% to 10.92%
6. organic horizon from 0 cm to 2.92 cm deep
Stream characteristics concerning where the cuttings should be placed on the channel are as follows:
1. as close as possible to 1.89 m from the wetted
channel
2. on a stream gradient from 2% to 27%
Planting depth should be as deep as possible inan attempt to ensure soil moisture throughout the growing season. 71
Should the transplanting of P. tremuloides(aspen) be desireable, the most critical aspect of siteselection is
stream gradient. The habitat requirements forP. tremuloides are only provided inareas of steep stream
gradient (approximately 19%). This speciesshould be
transplanted using sapling size (Table 2) cuttingsinto headwater stream ecosystems only. Surface soil
characteristics should be as follows:
1. pH from 7.2 to 7.8
2. soil macroporosity from 25.57% to 39.38%
3. sand content from 50.50% to 86.00%
4. coarse materials from 11.70% to 26.77%
5. soil organic matter content from 2.95% to7.27%
6. organic horizon from 0 cm to 1.68cm deep
Stream characteristics concerning where the cuttings
should be placed on the stream channelare as follows:
1. as close as possible to 3.15 m from the wetted channel
2. on a stream gradient from 13% to 27%
While these recommendations are basedon scientific research, the inherent problem of transplanting still remains -- a high degree of failure! The intention of making the above recommendations is to aid in the 72 increased percent survival of willow and aspen transplants. Fifty percent survival of the transplants may often be the highest one can expect. Transplanting is a valid means for riparian rehabilitation, especially if there are time frames involved. Invariably, public land managers are expected to take immediate action rather than to wait for natural processes. Riparian rehabilitation through the perpetuation of the Salicaceae by natural processes, is inherently more desireable than artificial transplanting. Transplanting should not be attempted until additional riparian recovery measures have been achieved (i.e. creation of the necessary surface soil characteristics). Unless natural processes are restored all plantings are doomed to failure. Rehabilitated riparian zones should be self-perpetuating sources of willows and cottonwoods. Even a successfully established willow stand is little more than an artificial habitat headed for eventual site degradaton, if the natural fluvial-biotic processes are not restored. Regardless of the means chosen for riparian enhancement, protection of the habitat through time is of paramount importance. 73
CONCLUSIONS The habitat of the Salicaceae is defined by any number of environmental and physiological processes. The previous discussion defines habitat in terms of 19 physical variables. This definition of habitat by no means recognizes all the processes which govern species-site selection.
This research can aid in establishing relevant management objectives based on the ecology of the species present, their requirements and inherent characteristics. Instead of the usual fence approximately 100 feet on either side of the stream, identification of the total riparian area intimately associated with the riparian vegetation must be considered when constructing fences.
Consequently, we may be better able to successfully administer these areas when they are managed as functional units rather than on an individualistic basis.
This research indicated that the Salicaceae, as a family, occupy specific habitats in terms of surface soil characterisitics. The Salicaceae require surface soils which have a mean pH of 7.3, a mean soil macroporosity of
27.08%, a mean sand content of 53.42%, a mean organic matter content of 6.0%, a mean coarse material content of
28.59%, and a mean organic horizon of 0.58cm. The remaining physical variables change for each species of the Salicaceae in time and space. 74
The variable of average stand distance from the wetted channel indicated the occurrence of shifts in the channel location of the streams studied. For all the species over the majority of size classes, this variable changed over time. This was attributed to the gradual meandering of the streams across their valleys.
Transplanting of willows and aspen to enhance riparian rehabilitation is very popular within the federal land management agencies. Just as prevalent is the high degree of failure of these endeavors. By identifying potential establishment sites based on surface soil characteristics as well as the associated physical characteristics of the stream, managers may be better able to select sites for successful rehabilitation.
Rehabilitation may be attempted either by natural processes or by transplanting.
The importance of riparian vegetation, especially members of the Salicaceae, has gained much notority from land managers and the concerned public. The realization that riparian vegetation is a significant component of the landscape for multiple uses, has even surfaced in the political arena. As such, society needs to have information available which is drawn from scientific research on which to base decisions. More research into the synecology of riparian zones and the autecology of the components of riparian zones is necessary for a more 75 complete understanding of these uniqueecosystems and their role in global ecology. 76
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Williams, B.K. 1983. Some observationson the use of discriminant analysis in ecology. Ecology 64(5):1283-1291. APPENDICES 82
Appendix A.
Site, Drainage, Exclosure Age and Salicaceous Dominant Species Identification. 83
Appendix A. Site, drainage, exclosure age and Salicaceous dominant species identification.
Exclosure Site No. Drainage Age Dominant
1 South Grizzly 9 S.lasiandra 2 S.lasiandra 93 S.lasiandra 95 S.lasiandra 30 S.lemmonii 31A S.lemmonii 31B S.lasiandra 3 S.lutea 32 S.lasiandra 96 S.lemmonii
4 North Grizzly 5 S.lasiandra
74 Gray Digger 5 P.tremuloides
75 Kings Gap 5 S.lasiandra 76 S.lasiandra 77 S.lasiandra 78 P.tremuloides 79 P.tremuloides
5 Skull Hollow 10 S.lasiandra 6 S.lasiandra 80A P.tremuloides 80B P.tremuloides 7 S.lemmonii 8 S.lasiandra 9 S.lutea 10 S.lemmonii 11 S.lutea 12 S.lemmonii 13 S.lutea 14 P.trichocarpa 15 S.lutea 16 P.tremuloides 100 S.lasiandra 17 S.lasiandra 20 S.lasiandra 21 S.lasiandra 22 S.lasiandra 23 S.lasiandra 24 S.lasiandra 25 S.lasiandra 26A S.lasiandra 84
26B S.lasiandra 27 S.lasiandra 28 S.lasiandra 29 S.lasiandra 33 S.lasiandra
34 Upper Lithgo 4 S.lasiandra 35 S.lasiandra 36 S.lasiandra 37 S.lasiandra 38 S.lasiandra 39 S.lutea 40 S.lutea 41 S.lemmonii 44 S.lasiandra 45 S.lutea 46 S.lasiandra 48 S.lutea 50 S.lutea
47 Lithgo 10 S.lasiandra 49 S.lutea 51 S.lutea 52 S.lasiandra 53 S.lutea 54 S.lutea 55 S.lutea 56 S.lasiandra 57 S.lutea 58 S.exiqua 59 P.trichocarpa 60 S.exigua 62 S.lutea 63 S.lasiandra 64 S.lasiandra 65 S.lasiandra 66 P.trichocarpa 67 S.lasiandra 68 S.lasiandra 69 S.lasiandra 70 S.lasiandra 71 S.lasiandra 72 S.lasiandra
81 Rodman 9 P.trichocarpa 117 S.lasiandra
82 East Haystack 29 S.exigua 83 S.exiqua
85 Haystack 29 S.lasiandra 87 S.exiqua 88 S.lemmonii 85
89 S.lutea 91 S.exiqua 94 S.lemmonii 97 S.exiqua 98 S.lutea 99 S.lasiandra 101 S.lasiandra 104 S.lutea 108 S.lasiandra 110 S.lemmonii 86 S.lasiandra
112 West Haystack 29 S.lasiandra 115 P.trichocarpa 116 S.lemmonii
92 Monner 4 P.trichocarpa
103 Culver P.trichocarpa
18 Cotman 9 P.tremuloides 102 S.lasiandra
105 Mud Springs 1 S.lasiandra 106 S.lasiandra 107 S.lasiandra 109 2 P.trichocarpa 118 S.lasiandra 119 S.lasiandra 120 S.lutea 123 P.trichocarpa
121 McMeen 9 S.lasiandra
124 Lone Pine 10 S.lasiandra 125 S.lasiandra 127 S.lasiandra 128 S.lasiandra 129 S.lasiandra 130 S.lasiandra 131 S.lasiandra 132 S.lasiandra 133 S.lasiandra
134 Cyrus 9 P.tremuloides 86
Appendix B.
Scientific Name, Common Name and Alpha Code of Plant
Species Occurring Within the Riparian ExclosuresAccording to the Nomenclature of Hitchcock and Cronquist (1973),
Garrison et al.(1976) and Kovalchik (1987). Appendix B. Scientific name, common name, and alpha code of plant speciesoccuring within the riparian exclosures according to the nomenclature of Hitchcock and Cronquist (1973), Garrison et al. (1976), and Kovalchik (1987).
GRASSES
Scientific Name Common Name Alpha Code
Agropyron caninum (L.) Beauv awned wheatgrass Agca Agropyron cristatum (L.) Gargrth. crested wheatgrass Agcr Agropyron dasystachvum (Hook.) Scribn. thick-spiked wheatgrass Agda Agropyron inerme (Scribn. and Smith) Rydb. beardless wheatgrass Agin Agropyron intermedium (Host) Beauv. intermediate wheatgrass Agin2 Agropyron repens (L.) Beauv. quackgrass Agre Agropyron spicatum (Pursh) Scribn. and Smith bluebunch wheatgrass AgsP Agrostis alba L. common bentgrass Agal Agrostis stolonifera (L.) Smith redtop Agst Agrostis tenuis Sibth. colonial bentgrass Agte Bromus mollis L. soft brome Brmo Bromus tectorum L. cheatgrass Brte Dactvlis glomerata L. orchardgrass Dabl Deschampsia cespitosa (L.) Beauv. tufted hairgrass Dece Elymus canadensis L. Canadian wildrye Elea Elymus cinereus Scribn. & Merr. giant wildrye Elci Elymus giganteus Vahl. Siberian wildrye Elgi Elvmus glaucus Buckl. blue wildrye Elgl Festuca californica Vasey California fescue Feca Festuca idahoensis Elmer Idaho fescue Feid Hordeum *ubatum L. foxtail barley Hoju Hordeum pusillum Nutt. little barley Hopu Koeleria cristata Pers. prairie junegrass Kocr Orvzopsis hymenoides (R. & S.) Ricker Indian ricegrass Orhy Phalaris caroliniana Watt. Carolina canarygrass Phca4 Phleum pratense L. common timothy Phpr Poa amnia Merrill big bluegrass Poam Poa bulbosa L. bulbous bluegrass Pobu Poa cusickii Vasey Cusick's bluegrass Pocu Poa nevadensis Vasey Nevada bluegrass Pone2 pratensis L. Kentucky bluegrass Popr Polvpogon monspeliensis (L.) Desf. annual beardgrass Pomo Sitanion hvstrix (Nutt.) Smith bottlebrush squirreltail Sihy Stipa occidentalis Thurb. Ex Wats western needlegrass Stoc Stipa thurberiana Piper Thurber's needlegrass Stth Taeniatherum caput-medusae L. medusahead Elca2
GRASSLIKES
Carex amplifolia Boott bigleaf sedge Caam Carex aquatilis Wahl. aquatic sedge Caaq Carex atherostachva Olney slenderbeaked sedge Caat Carex microptera Mack. smallwinged sedge Cami Carex nebrascensis Dewey Nebraska sedge Cane Carex rostrata Stokes beaked sedge Caor2 Carex stiptata Muhl. sawbeak sedge Cast Eleocharis palustris (L.) R. & S. creeping spikerush Elpa Eleocharis vauciflora (Lightf.) Link fewflowered spikerush Elpa2 Juncus balticus Wild. Baltic rush Juba Juncus bufonius L. toad rush Jubu Juncus confusus Coy. Colorado rush Juco Juncus ensifolius Wikst. dagger-leaf rush Juen Juncu4 howellii Herm. Howell's rush Julio Scirpus acutus Muhl. hardstem bulrush Scac Scirpus fluviatilis (Torr.) Gray river bulrush Scfl Scirpus olneyi Gray Olney's bulrush Scol Scirpus subterminalis Torr. water bulrush Scsu
FORBS
Achillea millefolium L. western yarrow Acmi Agastache urticifolia (Benth.) Kuntze nettleleaf horsemint Agur Amsinckia retrorsa Suksd. rigid fiddleneck Amre2 Antennaria dimorpha (Nutt.) T. & G. low pussytoes Andi Aouileizia formosa Fisch. Sitka columbine Aqfo Arnica chamissonis Less. leafy arnica Arch Artemisia ludoviciana Nutt. prairie sage Arlu Asclepias speciosa Torr. showy milkweed Assp Aster,campestris Nutt. meadow aster Asca2 Aster foliaceus Lindl. leafy bract aster Asfo Astragalus curvicarpos (She ld.) Macbr. curvepod locoweed Ascu2 Berula erecta (Huds.) Coy. cutleaved water parsnip Beer Boisduvalia densiflora (Lindl.) Wats. dense spikeprimrose Bode Calochortus macrocarpus Dougl. sagebrush mariposa lily Cama Castille'a sp. Mustis ex L.f. Indian paintbrush Castl Cerastium viscosum L. sticky chickweed Cevi Cicuta douglasii (DC) Coult. & Rose western waterhemlock Cid Circium cenovirens (Rydb.) Petr. grey-green thistle Cica2 Cirsium vulgare (Savi) Tenore bull thistle Civu Clarkia pulchella Pursh pink fairy Clpu Clematis ligusticifloia Nutt. western clematis Clli Collinsia varviflora Lindl. small flowered collinsia Copa Convolvulus arvensis L. field bindweed Coact C tvzu canadensis (L.) Cronq. horseweed Coca2 Crypthantha affmis (Grey) Greene slender cryptantha Cica2 Daucus carota (L.) Queen Anne's lace Daca4 Descurania richardsonii (Sweet) Schultz mountain tansymustard Deri Draba verna L. spring draba Drve2 Epilobium glaberrimum Barbey smooth willowweed Epgl Epilobium paniculatum Nutt. autumn willowweed Eppa Epilobium watsonii Barbey Watson's willowweed Epwa Equisetum arvense L. common horsetail Eqar Equisetum variegatum Schleich. varigated horsetail Eqva Erigeron philadelphicus L. Philadelphia fleabane Erph Eriogonum §vaerocephalum Dougl. rock buckwheat Ersp3 Eriogonum vimineum Dougl. broom buckwheat Ervi Erodium cicutarium (L.) L'Her. filaree Erci Fragaria vesca L. woods strawberry Frye Galium borale L. northern bedstraw Gabo Galium multiflorum Kell. shrubby bedstraw Gamu Geum macrophyllum Wild. Oregon avens Gama Hvpericum perforatum L. Klamath weed Hype Iris pseudocorus L. yellow iris Irps Lactuca serriola L. prickly lettuce Lase J .eppula redowskii (Harnem.) Greene western stickseed Lere Lithophragma parviflora (Hook.) Nutt. smallflowered prairiestar Lipa Lomatium donnellii Coult. & Rose Donnell's lomatium Lodo Lomatium triternatum (Plush) Coult. & Rose nineleaf lomatium Lotr Lotus purshiana (Benth.) Clements & Clements Spanish clover Lopu Lupinus lepidis Dougl. pririe, lupine Lule2 Lupinus leucophyllus Doug. velvet lupine Lule Madia gracilis (J.E. Smith) common tarweed Magr Medicago lupulina L. black medic Melu Melilotus officinale (L.) Lam. common yellow sweetclover Meof Mentha arvensis L. field mint Mear3 Microsteris gracilis (Hook.) Greene microsteris Migr Mimulus guttatus DC yellow monkeyflower Migu Moss Phacelia hastata Dougl. whiteleaf phacelia Phha Phlox hoodii Rich. Hood's phlox Phho Phlox muscoides Nutt. moss phlox Phmu2 Plantago major L. common plantain Plma Plectritis macrocera T. & G. white plectritis Plma3 Polygonum douglasii Greene prostrate knotweed Podo Potentilla biennis Greene biennial cinquefoil Pobi2 Potentilla gracilis Dougl. slender cinquefoil Pogr Ranunculus aquatilis L. water buttercup Raaq Rigiopappus leptocladus Gray bristlehead Rile Rorippa nasturtium-aauaticum (L.) Schinz & Thell. watercress Rona Rumex acetosella L. horse sorrel Ruac Salsola kali L. Russian thistle Saka Sisymbrium altissimum L. tumblemustard Sial Solanum dulcamara L. climbing nightshade Sodu2 Solidago occidentalis (Nutt.) T. & G. western goldenrod Sooc2 Sonchus asper (L.) Hill prickly sowthistle Soas Stephanomeria tenuiflora (Torr.) Hall narrowleaved skeletonweed Stte Taraxacum officinale Weber common dandelion Taof Tragopogon dubius Scop. yellow salsify Trdu Trifolium repens L. white clover Trre Trifolium wormsioldii Lehm. springbank clover Trwo2 Typha latifolia L. common cattail Ty la Urtica dioica L. slim nettle Urdi Verbascum blattaria L. moth mullein Vebl Verbascum thapsis L. common mullein Veth Veronica americana Schwein. American speedwell Veam Vida americana Muhl. American vetch Viam Viola adunca Sm. early blue violet Viad Xanthium strumarium L. common cocklebur Xast Zigadenus veneosus Wats. meadow death camus Zive
SHRUBS
Amelanchier alnifolia Nutt. western snowberry Amac Artemisia arbuscula Nutt. low sagebrush Arar Artemisia rigida (Nutt.) Gray stiff sagebrush Arri Artemisia tridentata ssp. tridentata Nutt. basin big sagebrush Artrt Artemisia tridentata ssp. vaseyana Nutt. mountain big sagebrush Artry Chrysothamnus nauseosus (Pall.) Britt. gray rabbitbrush Chna Chrysothamnus viscidiflorus (Hook.) Nutt. green rabbitbrush Chvi Comus stolonifera Michx. red osier dogwood Cost Lycium halmifolium Mill. matrimony vine Lyha Philadelphicus lewisii Pursh Lewis mockorange Phle2 Prunus emarginata (Dougl.) Walp. bittercherry Prem Prunus vireiniana L. common chokecherry Prvi Purshia tridentata (Pursh) DC. wax currant Rice Rosa nutkana Fern bristly Nootka rose Ronu Rosa Awl ii Lindl. Wood's rose Rowo Salix exigua Nutt. coyote willow Saex Salix lasiandra Benth. peachleaf willow Sala2 Salix lemmonii Bebb. Lemmons willow Sale Salix lutes Nutt. yellow willow Salu Sambucus cerulea Raf. blue elderberry Sace Svmphoricarpos occidentalis Hook. western snowberry Syoc
TREES
AWLS imam (L.) Moerch. thinleaf alder Alin Betula occidentalis Hook. water birch Beoc Juniperus occidentalis Hook. western juniper Juoc Pinus ponderosa Dougl. Ex Loud. ponderosa pine Pipo Populus tremuloides Michx. quaking aspen Potr Populus trichocarpa T. & G. black cottonwood Potr2 94
Appendix C. Acronyms of the Physical Variables. 95
Appendix C. Acronyms for the physical variables.
Vegetation
Stand distance from wetted channel DIST FROM
Riparian zone width RIP ZONE
Exclosure age EXLOSURE
Water
Wetted channel width WET CHAN
Stream gradient GRADIENT
Soils
Bulk density BD
Macroporosity MP Depth to an impenetrable layer IMPENETR
Depth to a gleyed horizon GLEYED
Depth of an organic horizon 0 HORIZON
Percent coarse materials COARSE
Percent fine materials FINE Percent organic matter OM
Percent clay CLAY
Percent sand SAND
Percent silt SILT
Soil pH PH 96
Other
Aspect ASPECT
Elevation ELEVATION 97
Appendix D.
Canonical Discriminant Function Scores for the Salicaceous Species According to Size Class. 98
Appendix D. Canonical Discriminant Function Scores for Saticaceous Species According to Size Class.
SAPLING (A - S. lasiandra, B - S. tutee, C - S. lemmonii, E - P. tremuloides F S. exigua)
SPECIES CDF 1 CDF 2 CDF 3 CDF 4
B 0.91199-0.58548-1.36494 0.23802 C 3.09132-0.42187-0.28682-0.60161 0.21639 2.46949-1.63923 0.01443 C 3.03020-0.33994 0.33367-1.70701 A -0.17132-2.26829 0.49315-1.40009 A -0.42823-2.08290-1.38367 0.29145 C 3.40923-0.73714-1.88999-2.52918 A -0.64074 0.408840.285780.94262 A -2.62146 0.34528 0.10553 0.16857 B -1.17450 1.05817-2.29106-0.69892
13 -0.905371.01583-2.35609 1.72515 B -1.05391-0.09838 0.399470.13829 F -2.157500.90142 2.83471-0.17588 A -2.13151 0.39280 1.53605 0.33035 F -1.58192 1.28785 1.30795 0.10705 A -0.96108-2.13317-0.09730-0.20659 A -0.88210-1.02167-1.21831-1.81906 A -0.27529-0.71315-0.70857 0.63670 E 2.999620.83899 1.27380 1.45282 A -0.12876-0.79946-0.43389 0.40611 E 1.39482 0.52625-0.065272.16095 E 3.94840 0.61831 1.97414 0.06108 E 3.75205 0.56699 0.147820.30785 A -1.75475-2.30792-0.74700 1.35289 B -1.22739 1.11861 0.09483-1.90920 F -1.009342.92039-0.14118-0.95945 A 1.84219-0.60178 1.47521-0.31933 A -1.19076-1.64212 0.05114-0.59343 C 4.36717-0.77112 1.33319 0.80107 F -2.49815 2.807402.26516-0.97317 B -0.493603.65578-0.86676-0.42225 A -2.85447-1.572760.24707-0.09009 B 0.602732.48459-1.90542 1.53538 A -1.59247-1.824390.458520.03596 A -0.36146-1.69553 0.51508 1.42517 A -1.47000-1.791950.26322 0.27333 99
INTERMEDIATE (A - S. lesiandre, B -S. lute., C - S. lemmonii)
SPECIES CDF 1 CDF 2 CDF 3 COF 4
A -1.46321-0.099620.09795 0.53119 A 0.44561-0.61132-1.38055-1.18018 A 0.01993 1.07569-1.19251-0.61694 B 0.51216-3.661064.34557-0.99980 C 2.892870.65732-0.93254-1.54287 B 0.63769-1.58281-0.75193 1.19762 B 1.24338 0.29961-0.76328-0.02571 A 0.69182 1.875880.70896-0.21680 A -1.19021 0.478470.87320-0.11867 A -1.02618 1.75043 1.03181-0.14895 A -1.41073 0.74703 1.25293-0.32039 A 0.04115 0.77558 0.09736-0.35972 A -0.26758 1.212030.72430-0.92311 C 5.555190.91958 0.59042-1.49900 A 0.181652.01849 0.58750 1.01517 A 0.63552-1.00430 0.09161 0.83788 A -1.122500.00118 0.413030.40402 A -0.55416-1.78448-1.03576 1.29351 C 5.45553 1.168270.34212 3.04187 B -0.50799-0.04126-0.39156-0.28180 1.34258-2.60562-0.38466-0.14573 B -1.11293-1.71076-0.39165 0.60166 A -2.31304-0.82376-0.88878 0.80814 B 1.66414-3.17362-0.45633-1.27422 A 0.05924-0.72111-0.87548-0.90546 B -0.15431-1.37860-0.472390.72923 A -0.73742 0.03471 0.36124 0.02374 A -0.15642 1.12011 0.65282-0.19057 A -0.06604-0.42552-0.18274 1.68214 A -0.913870.473360.840720.33627 A 1.48889 0.01756-0.94726-0.81605 A -0.916181.63691-0.60262-0.02999 B -0.59193-1.97723-0.733760.19875 A 0.33683-0.329890.27082 1.05297 A -1.79582 0.79425 0.53643 0.80845 A -0.33746 0.51463-0.52739-1.17572 A -0.50439 0.822480.839660.22062 A -2.78246-0.07761 0.04620-0.63784 A -1.125270.39263-0.91829 1.58351 A 0.00660 1.09926-0.46531 1.20839 A -0.04402 1.668430.13878-0.65659 A -2.116680.45469-0.54861-0.34200 100
DECADENT (A - S. tasiondra, 8 - S. tutea, C - S. temmonii, D - P. trichpcarpa, E P. tremutoides, F S. exigua)
SPECIES CDF 1 CDF 2 CDF 3 CDF 4
A -0.29965 1.87516-0.293792.26800 A -1.10835 1.51062-1.08374 1.68105 A -1.75349 0.997670.072730.35513 D 3.30657 0.92951-0.23764-1.10821 E 3.163280.946790.03409-1.39131 E 4.787770.61745 0.181680.74478 A 0.79444 0.546400.55388-1.53888 A -0.57688 1.33327-0.47799 0.40052 A -1.88340 1.28915-0.91732 0.62829 A -1.82999 0.80892-0.005900.60181 A 1.24298 1.31816-0.50441-0.00973 A -1.45436 2.22645 0.492870.12847 A -1.30058 1.80465 0.46017-0.52441 B -0.91887 1.50603 0.58660-0.50580 B 0.08254 1.74335 0.74824-1.69338 A -2.06078 1.890800.14705 0.43310 B 0.13676 1.90441 0.508070.96158 A -0.33937 1.61357 1.27635 0.49906 B -1.231993.047204.60214-1.12621 F -2.90654-0.94445-0.70081 0.53898 D -0.04113-1.49498 2.539300.16038 D 0.19163-2.19384-1.77147-2.29992 A 0.01317 1.798190.27635 0.58804 A -0.02244 0.85348 0.60211-1.10885 A -0.25292-0.16127-1.46624 0.87320 E 3.86026 1.50276-0.88619 1.02087 D -0.66317-1.13472-0.60473-0.93461 F -2.11165-1.89087-0.86932-0.57994 F -3.09015-0.92249-0.905650.77960 A -0.24505-2.45777 1.66532 1.78686 F -1.26904-3.53540-0.46326 1.78484 C 1.19749-4.01259 1.072220.93294 D -1.22178-1.41678-1.02366-0.39081 C 1.18077-4.09659 1.77331 0.84573 D 0.45214-1.24262-1.20450-1.48923 A -0.53343 0.56107-0.40997-0.42485 A -2.00631 0.64970-1.06565-0.68895 A -0.329350.34153-0.84415-0.33133 D 0.44276-0.56841-1.187830.22246 C 1.75337-2.37673 1.829520.69117 D 1.39724-2.38944 0.41399-1.50023 101
Appendix E. Values of the Physical Variables. 102
Appendix E. Values of Physical Variables
stand pH MP BD clay sand silt OM gcm-3 X % % %
1 7.4 30.13 0.7124 12.1 70.9 17.0 6.10 2 7.0 23.24 0.5330 13.2 72.1 14.8 5.52 3 6.8 30.66 0.8706 10.8 78.1 11.1 3.78 4 6.6 19.16 0.8063 23.7 38.9 37.6 6.48 5 7.6 21.74 0.8175 27.6 53.3 19.2 3.63 6 8.1 11.40 1.5103 24.1 57.7 18.2 9.30 7 7.4 28.93 0.7866 31.1 40.2 28.7 7.34 8 7.3 24.38 1.0005 32.0 49.2 18.8 8.36 9 7.0 23.80 0.9949 23.0 55.2 21.9 11.99 10 7.4 32.33 0.7670 28.1 42.1 29.8 12.98 11 7.4 29.49 1.2314 21.2 73.5 5.4 4.18 12 7.1 26.26 0.8224 31.7 37.2 31.2 7.60 13 7.4 30.38 0.7457 29.3 52.1 18.7 4.34 14 7.8 37.17 0.9326 18.9 54.0 27.3 8.73 15 7.3 33.01 0.7815 24.3 49.7 26.0 7.61 16 7.3 36.71 0.9875 23.8 53.6 22.6 7.03 17 7.3 36.11 0.5449 33.8 31.8 34.5 8.18 18 6.9 45.79 0.4735 18.3 54.6 27.1 4.74 20 6.7 31.28 0.8414 33.7 41.9 24.5 8.54 21 7.4 28.58 0.9529 29.6 46.0 24.6 4.33 22 7.6 25.96 0.5697 37.5 32.6 30.0 5.36 23 7.5 19.01 0.9251 37.8 37.6 24.8 5.44 24 7.4 21.75 1.1121 33.4 38.8 27.9 7.51 25 7.7 32.07 0.6903 27.2 34.8 38.1 7.98 26 A 7.5 21.01 0.9323 46.2 25.6 28.2 6.63 26 B 7.3 15.99 0.8652 33.9 35.1 31.1 6.19 27 7.8 15.62 0.8884 42.3 34.8 22.9 6.47 28 7.4 20.02 1.1382 34.3 46.2 19.6 4.14 29 7.6 11.55 1.0637 36.4 40.7 23.0 10.92 30 6.6 33.02 0.4929 14.6 61.9 23.6 19.17 31 A 6.2 23.49 0.7873 21.4 38.2 40.5 9.13 31 B 7.0 29.37 0.5927 22.6 46.3 31.1 7.64 32 7.0 35.09 0.8103 12.2 74.5 13.3 4.24 33 7.0 39.35 0.6793 24.0 46.4 29.7 5.88 34 7.8 34.87 1.3839 20.6 65.3 14.2 2.81 35 7.4 19.19 1.3027 30.5 57.4 12.2 3.30 36 7.6 21.78 1.0121 24.0 52.9 23.2 7.09 37 7.3 32.46 0.6865 33.1 38.2 28.8 5.38 38 7.1 33.99 0.8280 22.6 56.5 20.9 3.57 39 7.4 25.47 1.2345 24.4 67.8 7.8 2.66 40 7.3 24.08 1.3072 30.4 50.8 18.9 4.11 41 7.4 69.04 0.8593 23.3 56.3 20.4 2.09 44 7.6 19.35 1.1800 18.1 75.3 6.8 3.31 45 7.0 35.25 0.7987 11.3 70.8 18.0 6.28 46 7.5 26.89 1.7367 10.0 84.1 6.0 1.81 47 6.9 13.05 1.3183 10.6 80.7 8.8 3.43 103
48 7.3 30.16 0.9229 22.5 49.8 27.7 7.15 49 7.9 27.39 1.2902 13.7 76.0 10.4 5.74 50 7.0 34.29 0.9303 22.0 66.8 11.3 4.22 51 7.2 29.51 1.0285 20.4 67.7 12.0 3.02 52 7.0 15.54 0.9946 28.9 49.1 22.0 5.26 53 7.2 17.83 0.7193 16.1 65.1 18.9 12.89 54 7.0 16.41 0.8693 15.2 28.2 56.7 37.22 55 7.3 27.16 1.1626 16.4 68.5 15.2 7.85 56 6.7 32.74 0.6965 26.1 48.3 25.6 9.07 57 7.8 22.29 1.1124 25.3 46.5 28.3 6.31 58 7.3 24.48 0.8082 15.7 50.4 33.9 7.85 59 6.9 20.55 1.1651 30.0 41.0 29.1 6.67 60 7.4 29.70 0.8291 16.8 73.2 10.1 2.63 62 7.1 20.16 0.9821 22.3 58.3 19.4 5.73 63 7.1 39.60 0.6023 12.7 76.5 10.9 5.02 64 7.1 32.63 0.9642 21.8 59.3 19.0 4.02 65 7.2 34.60 1.0260 9.2 82.9 8.0 1.82 66 7.6 35.58 0.7109 19.4 55.2 25.5 5.24 67 7.0 37.18 0.8545 23.5 56.1 20.5 5.90 68 7.4 32.73 0.8917 18.3 62.2 19.6 3.65 69 7.2 31.14 0.6486 20.5 53.4 26.2 9.67 70 7.3 33.44 0.8336 20.4 59.8 19.9 4.35 71 6.8 22.55 1.2647 21.2 53.2 25.6 7.00 72 7.5 41.09 0.7342 22.3 48.0 29.7 5.72 74 7.2 39.38 0.8832 7.1 81.4 11.6 2.95 75 7.1 13.74 1.0836 6.4 82.2 11.5 1.98 76 7.0 19.83 1.3330 18.1 70.9 11.1 3.09 77 6.8 16.55 1.1126 19.4 58.8 21.9 6.49 78 7.8 25.57 0.6313 10.5 86.0 3.6 3.86 79 7.3 43.67 0.8520 1.4 93.5 5.3 2.32 80 A 7.4 26.81 0.7980 23.7 50.5 25.9 6.08 80 B 7.2 37.63 0.8823 23.3 50.5 26.3 7.27 81 7.8 21.44 1.0832 22.9 27.1 50.0 6.14 82 7.4 24.64 0.9282 9.7 84.0 6.5 2.37 83 7.0 18.88 1.1259 7.5 85.8 6.7 1.27 85 7.2 24.88 0.8764 23.1 39.9 37.1 10.06 86 6.9 25.19 1.0296 12.5 63.0 24.6 4.87 87 8.0 21.24 1.0436 16.8 59.2 24.0 2.39 88 7.3 33.28 1.0763 15.3 59.7 25.0 6.79 89 6.6 20.12 1.0057 28.8 20.5 50.8 7.28 91 7.1 29.48 0.9290 30.4 28.8 40.9 5.64 92 7.4 30.71 0.8074 12.1 71.9 16.1 3.91 93 7.1 21.57 0.5481 17.2 70.5 12.4 6.02 94 6.7 25.89 0.9570 16.7 56.8 26.6 5.10 95 7.0 33.75 0.2981 25.0 41.1 34.0 2.43 96 7.1 32.43 0.8522 12.5 75.7 11.9 3.76 97 7.4 18.70 0.6022 34.4 18.1 47.7 6.16 98 7.2 34.16 0.6761 31.4 27.6 41.1 8.59 99 7.7 30.96 0.7727 40.0 34.8 25.3 6.55 100 7.8 14.72 0.7612 26.1 59.3 14.6 3.00 101 7.3 30.38 0.5951 32.1 13.2 54.7 12.08 102 6.8 19.32 0.8886 42.3 29.3 28.4 8.26 104
103 7.4 25.73 1.0713 16.6 65.3 18.1 4.79 104 7.5 15.45 1.0966 31.9 11.3 56.9 9.38 105 7.6 21.30 1.2284 10.3 82.9 6.8 3.77 106 9.1 13.93 0.7995 19.5 44.9 35.7 9.11 107 8.9 21.72 0.8843 10.3 48.7 41.1 8.59 108 8.0 24.19 1.0343 19.4 59.2 21.4 3.55 109 7.7 32.60 0.7297 13.5 75.7 11.0 1.74 110 6.9 32.88 1.0519 15.4 58.9 25.8 5.66 112 6.9 25.25 0.8454 24.1 2.9 73.1 4.63 115 7.3 25.93 0.9849 21.4 34.8 43.9 3.01 116 7.0 22.93 0.8888 20.5 21.9 57.7 3.18 117 7.7 22.96 0.8853 24.1 20.1 55.9 7.58 118 8.3 24.61 0.9071 13.2 58.2 28.7 1.84 119 8.2 8.46 1.1765 15.9 60.0 24.2 2.17 120 7.7 34.50 0.6234 20.1 42.0 38.1 7.25 121 7.2 29.78 0.2400 31.2 40.8 289.0 7.16 123 7.5 27.97 0.8195 23.8 30.5 45.9 3.22 124 6.9 34.63 1.0215 13.8 64.3 22.0 2.77 125 7.0 30.53 0.8377 14.5 71.6 13.9 2.46 127 8.1 25.16 0.8788 17.1 45.7 37.3 12.13 128 7.3 11.72 0.8631 17.3 57.9 24.8 5.45 129 6.6 13.28 0.9137 16.1 29.1 55.0 4.32 130 6.5 29.70 0.8154 19.1 32.6 48.3 4.36 131 7.5 34.37 1.1033 12.1 79.3 8.7 2.95 132 7.8 28.79 1.0732 7.5 83.9 8.6 1.98 133 7.7 29.25 0.9507 6.3 93.5 0.2 0.56 134 7.5 33.12 0.7550 21.8 24.6 33.6 6.57 105
diameter widest stand area crown base height length width cover stand (cm) (m) (m) (m) (.2)
1 52.20 10.00 10.35 9.50 77.37 2 39.47 7.62 5.80 9.60 46.57 93 1.04 0.60 11.87 0.68 30.93 95 1.04 0.95 10.00 24.20 229.66 30 12.86 3.66 5.00 5.10 20.03 31 A 0.32 3.05 9.50 4.00 35.78 31 B 47.11 4.27 11.90 6.35 65.48 3 1.50 3.96 6.10 6.95 33.44 32 2.57 6.31 9.29 9.91 72.38 96 0.86 0.75 1.40 1.49 1.64 4 30.00 2.13 2.00 4.06 7.21 74 1.47 0.54 3.110 3.22 9.68 75 1.50 1.09 2.20 0.95 1.95 76 11.00 1.00 2.30 1.20 2.41 77 20.37 7.31 10.82 9.61 81.95 78 1.33 1.57 10.33 5.03 46.32 79 7.80 3.39 4.31 2.40 8.84 5 2.95 1.83 1.06 0.90 0.75 6 2.12 1.68 0.78 1.90 1.41 80 A 3.02 17.37 11.07 12.10 105.41 80 B 4.38 2.02 9.50 2.35 27.57 7 5.99 5.49 4.55 5.10 18.28 8 2.90 25.50 6.00 5.80 27.34 9 3.79 7.77 11.70 4.00 48.40 10 6.77 3.05 19.20 7.40 138.93
11 2.04 1.07 2.67 1.85 4.01 12 5.73 3.96 8.65 6.20 43.30 13 6.62 2.44 5.41 4.75 20.27 14 32.47 30.48 2.19 1.22 2.28 15 5.42 1.22 4.40 4.67 16.15 16 8.20 2.74 2.40 2.50 4.71 100 1.02 0.90 0.77 0.39 0.26 17 5.19 3.05 2.60 2.79 5.70 20 35.01 5.62 16.00 12.35 157.81 21 3.80 3.02 24.22 6.60 186.51 22 6.99 3.33 3.04 2.32 5.64 23 5.47 5.17 10.55 8.49 71.18 24 2.77 2.02 4.08 5.46 17.87 25 4.79 1.99 5.22 3.51 14.96 26 A 39.79 7.08 6.81 9.28 50.83 26 B 1.60 2.20 0.89 1.43 1.06 27 50.29 8.18 6.32 6.67 33.13 28 40.74 5.67 7.32 9.50 55.55 29 1.38 1.58 3.02 2.09 5.13 33 8.66 2.75 6.07 5.40 25.83 34 0.81 0.50 0.24 0.46 0.10 35 28.97 9.08 11.02 7.97 70.81 106
36 41.06 10.11 5.77 4.58 21.03 37 15.28 2.90 2.90 3.00 6.83 38 14.64 4.38 4.91 4.36 16.87 39 19.74 5.28 5.49 6.24 27.02 40 29.29 4.44 5.08 6.04 24.28 41 10.25 4.34 5.08 8.34 35.36 44 31.51 7.25 4.14 6.72 23.16 45 17.19 4.72 7.77 9.86 61.03 46 46.16 10.98 7.83 6.74 41.68 48 4.60 2.71 3.22 4.81 12.66 50 2.95 1.99 2.47 3.43 6.83 47 1.21 1.09 1.15 1.06 0.96 49 5.29 6.78 9.04 9.01 63.97 51 4.18 2.87 5.06 4.75 18.90 52 2.11 2.08 1.11 1.02 0.89 53 7.51 3.35 3.92 3.38 10.46 54 13.32 4.13 7.13 7.66 42.95 55 1.86 1.21 0.49 0.52 0.20 56 3.74 2.92 2.55 3.43 7.02 57 2.63 3.32 1.08 2.29 2.23 58 9.72 7.19 25.32 10.05 245.64 59 39.79 16.11 8.49 11.48 78.30 60 2.90 2.17 2.71 2.00 4.36 62 6.28 3.09 5.81 4.99 22.90 63 1.21 2.01 2.22 2.47 4.32 64 4.03 3.81 3.79 3.21 9.62 65 2.06 1.17 1.11 1.07 0.93 66 53.79 33.84 29.06 21.30 497.97 67 3.52 3.99 3.20 2.77 7.00 68 36.29 6.40 8.02 11.58 75.43 69 1.05 1.33 0.98 1.01 0.78 70 32.47 8.53 13.63 11.81 127.08 71 0.95 0.98 0.61 0.57 0.27 72 1.97 1.94 1.86 1.67 2.45 81 79.90 14.72 9.81 9.33 71.93 117 5.97 1.69 2.50 2.83 5.58 82 4.93 2.73 22.11 34.28 624.36 83 3.84 2.97 44.78 36.16 1286.34 85 0.16 5.93 7.74 7.44 45.25 87 6.10 5.21 20.74 21.29 346.86 88 23.87 12.57 9.88 14.68 118.44 89 2.40 2.03 5.94 5.98 27.90 91 2.40 3.63 41.96 24.67 871.70 94 21.96 10.61 9.03 6.05 44.65 97 2.74 3.15 25.82 26.28 532.97 98 1.33 1.53 2.76 2.88 6.25 99 2.27 1.28 3.34 2.32 6.29 101 2.11 2.56 6.65 7.25 37.94 104 3.08 2.01 4.26 5.34 18.10 108 3.02 1.97 2.96 3.55 8.32 110 20.37 7.64 6.48 6.80 34.63 86 21.60 2.13 7.58 6.52 39.04 107
112 4.89 3.06 4.70 4.74 17.50 115 42.97 21.42 22.34 24.30 427.12 116 22.28 13.04 8.34 7.79 51.09 92 78.94 19.57 13.77 10.75 118.05 103 48.51 14.73 43.28 18.82 757.20 18 12.73 9.70 31.20 13.90 399.38 102 9.42 3.74 4.39 3.92 13.56 105 36.29 9.08 5.19 5.12 20.87 106 53.16 9.26 6.02 5.91 27.95 107 49.02 9.34 7.38 6.03 35.31 109 52.20 13.42 5.48 10.13 47.84 118 2.55 3.31 2.60 2.87 5.87 119 3.08 2.91 3.44 2.95 8.02 120 2.00 2.64 3.28 3.45 8.89 123 25.40 10.47 8.71 6.61 46.08 121 4.25 3.81 4.98 4.51 17.68 124 1.67 2.08 3.10 3.10 7.55 125 3.98 2.44 2.07 2.65 4.37 127 41.38 7.09 5.42 5.34 22.73 128 1.16 1.17 1.06 0.74 0.64 129 1.24 1.70 1.58 1.93 2.42 130 43.93 10.90 4.88 4.80 18.40 131 32.15 9.51 5.19 7.38 31.02 132 27.38 8.90 5.17 4.00 16.51 133 3.00 3.05 4.18 4.59 15.10 134 13.69 7.78 15.34 15.81 190.52 108
depth to depth of 0 impenetr. depth to horizon layer gleyima stand (cm) (m) (m)
0.15 ** 1 2.39 ** 2 0.64 0.18 ** 93 0.56 0.30 ** 95 1.42 0.24 0.30 30 0.33 0.85 ** 31 A 0.18 0.07 ** 31 B 0.79 0.09 ** 3 1.35 0.15 ** 32 0.64 0.77 ** 96 1.27 1.01 ** 4 0.79 0.31 ** 74 0.00 0.38 ** 75 2.62 0.19 ** 76 0.79 0.40 0.46 77 0.00 1.01 ** 78 1.68 0.30 ** 79 0.00 1.01 ** 5 0.00 0.22 ** 6 0.00 0.20 ** 80 A 0.00 1.01 80 B 0.00 1.01 " ** 7 0.00 0.87 ** 8 0.00 0.61 9 0.48 0.17 ** ** 10 0.79 0.26 ** 11 0.00 0.14 ** 12 0.00 1.01 ** 13 0.00 0.03 ** 14 0.00 1.01 ** 15 0.33 0.21 16 0.00 0.71 ** ** 100 1.60 0.27 ** 17 0.00 0.26 ** 20 0.00 0.24 ** 21 0.00 0.21 0.46 22 2.69 0.92 23 2.06 0.41 0.46 0.47 24 1.27 0.49 ** 25 0.15 0.60 ** 26 A 0.33 0.89 0.36 26 B 0.00 1.01 ** 27 0.00 0.74 28 0.00 0.70 ** 0.02 29 0.00 0.83 ** 33 0.00 0.09 34 0.00 0.16 ** 35 0.33 0.32 ** 109
36 0.00 0.17 ** 37 0.15 0.20 ** 38 0.00 0.00 ** 39 0.00 0.02 ** 40 0.00 0.04 ** 41 0.00 0.04 ** 44 0.00 0.32 ** 45 0.00 0.92 ** 46 0.00 1.01 ** 48 0.00 0.20 ** 50 0.00 0.38 0.33 47 0.33 0.12 0.08 49 0.33 0.10 ** 51 0.00 0.10 ** 52 0.00 0.46 0.23 53 0.97 0.16 0.11 54 2.06 0.32 ** 55 0.00 0.14 0.08 56 1.75 0.12 ** 57 0.00 0.08 ** 58 1.75 0.43 0.18 59 0.56 0.16 ** 60 0.00 0.08 ** 62 1.60 0.16 0.13 63 0.00 0.00 *r 64 0.79 0.13 ** 65 0.00 0.00 ** 66 0.25 ** 0.08 67 0.00 0.51 ** 68 0.48 0.80 ** 69 0.97 0.47 ** 70 0.00 ** ** 71 0.64 0.13 ** 72 0.15 0.29 ** 81 1.52 1.01 ** 117 0.00 0.30 ** 82 0.02 0.25 ** 83 0.00 1.01 ** 85 1.27 1.01 ** 87 1.68 1.01 ** 88 1.60 1.01 ** 89 1.04 1.01 ** 91 0.48 1.01 ** 94 0.00 1.01 ** 97 0.56 1.01 ** 98 0.08 1.01 ** 99 0.33 1.01 ** 101 0.89 1.01 ** 104 0.00 1.01 ** 108 0.64 0.47 0.30 110 1.27 1.01 ** 86 1.52 1.01 ** 110
112 0.48 0.62 ** 115 0.48 0.73 ** 116 1.27 1.01 ** 92 0.56 0.56 ** 103 0.00 1.01 ** 18 0.00 1.01 ** 102 2.08 0.65 ** 105 0.00 1.01 ** 106 2.69 0.13 ** 107 1.83 1.01 ** 109 0.00 1.01 ** 118 0.00 1.01 ** 119 0.48 1.01 ** 120 1.19 0.67 ** 123 0.15 1.01 ** 121 3.18 0.38 ** 124 1.12 1.01 ** 125 0.00 1.01 0.08 127 0.00 1.01 ** 128 0.41 1.01 0.04 129 1.04 1.01 0.02 130 1.52 1.01 ** 131 0.15 1.01 ** 132 0.15 1.01 ** 133 0.00 1.01 ** 134 2.06 1.01 ** 111
wetted channel rip zone distance from width width wetted channel stand (m) (m) (m)
1 1.09 9.60 0.48 2 1.16 3.95 1.83 93 12.50 23.00 in channel 95 1.56 7.96 in channel 30 2.74 5.80 8.77 31 A 1.52 21.00 1.22 31 B 1.52 21.00 1.22 3 0.89 8.93 1.97 32 1.10 22.75 in channel 96 1.16 5.65 0.98 4 7.75 30.00 in channel 74 1.12 10.89 0.64 75 0.51 10.00 0.78 76 0.98 7.02 1.94 77 2.39 14.97 in channel 78 0.45 9.87 1.44 79 2.52 9.03 2.85 5 0.70 3.00 in channel 6 0.40 2.60 in channel 80 A 0.70 5.50 3.15 80 B 0.70 5.50 2.85 7 1.00 3.75 1.24 8 0.70 3.65 1.40 9 0.75 4.00 1.50 10 0.45 12.00 4.50 11 0.85 1.85 0.03 12 0.55 4.47 3.00 13 0.50 3.18 3.50 14 1.05 4.20 1.52 15 1.59 3.40 1.37 16 0.60 2.20 1.73 100 0.38 3.25 0.09 17 0.50 2.27 0.05 20 2.01 4.55 1.52 21 0.66 6.58 in channel 22 1.92 7.18 0.65 23 5.43 7.64 1.02 24 2.25 5.20 in channel 25 0.82 2.47 0.55 26 A 2.09 5.79 0.54 26 B 1.24 6.10 in channel 27 0.24 6.93 1.35 28 0.69 5.96 1.00 29 1.42 2.64 0.16 33 2.91 3.69 0.79 34 2.55 2.41 in channel 35 0.51 2.44 1.96 36 0.88 3.48 0.60 112 86 110 108 104 101 99 98 97 94 91 89 88 87 85 83 82 117 81 72 71 70 69 68 67 66 65 64 63 62 60 59 58 57 56 55 54 53 52 51 49 47 50 48 46 45 44 41 40 39 38 37
** *. ** ** ** ** ** 547.62 547.62 547.62 547.62 547.62 547.62 547.62 547.62 547.62 547.62 0.47 1.82 0.41 1.02 0.71 5.46 1.08 2.01 0.55 0.43 0.53 0.66 0.96 0.85 0.91 0.85 0.90 0.74 0.60 1.46 0.60 0.89 0.54 0.68 0.33 0.61 1.46 0.69 0.44 0.84 1.00 1.06 1.20 0.83 0.71
152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 152.40 44.78 34.28 16.01 10.46 1.67 2.91 5.38 5.46 6.59 2.23 7.55 6.79 6.79 10.98 2.68 3.24 89.00 4.06 5.69 7.12 0.99 6.09 6.03 9.15 4.61 5.48 3.57 5.78 1.27 13.41 13.41 8.88 12.83 12.83 1.75 2.82 1.32 in in 64.01 73.15 68.58 36.58 109.73 73.15 118.87 118.87 109.73 100.58 91.44 82.30 73.15 68.58 45.72 5.33 14.21 0.11 12.04 1.21 1.81 0.78 0.52 1.89 1.87 1.38 channel 0.58 channel 2.09 0.10 85.00 0.46 15.22 13.12 0.19 1.17 1.31 0.11 3.01 2.09 0.82 0.99 1.88 1.77 0.21 5.71 4.38 0.95 0.66 0.55 0.29
112 113
115 ** 152.40 54.86 116 ** 152.40 64.01 92 2.31 14.33 1.21 103 1.83 7.01 2.57 18 ** ** ** 102 ** ** ** 105 7.53 13.32 1.10 106 10.14 26.10 0.43 107 2.09 23.00 2.20 109 2.41 4.11 2.04 118 3.23 7.67 0.47 119 7.50 8.99 0.15 120 5.65 10.60 2.21 123 3.81 6.96 2.26 121 22.82 36.47 8.42 124 1.44 9.35 1.90 125 7.14 9.33 in channel 127 12.00 15.00 1.04 128 5.56 10.11 0.67 129 6.75 8.93 in channel 130 7.00 12.00 in channel 131 5.52 12.02 in channel 132 1.49 9.81 in channel 133 2.53 9.96 in channel 134 ** * * * * 114
exclosure gradient aspect elevation age stand (X) ( ) (111) (yrs)
1 25 315 1207 0 2 25 315 1188 9 93 25 315 1188 9 95 25 315 1207 9 30 25 315 1204 9 31 A 25 315 1204 9 31 8 25 315 1204 9 3 25 315 1173 9 32 25 315 1181 9 96 29 315 1204 9 4 16 270 1158 5
74 20 270 1173 5 75 27 270 1170 5
76 27 270 1164 5
77 27 270 1164 5
78 27 270 1151 5
79 27 270 1149 5 5 15 180 1006 10 6 15 180 1009 10 80 A 15 180 1009 10 80 8 13 180 1009 10 7 13 180 1018 10 8 13 180 1024 10 9 13 180 1024 10 10 13 180 1029 10 11 13 225 1029 10 12 13 180 1029 10 13 13 180 1036 10 14 13 180 1039 10 15 13 180 1039 10 16 13 180 1055 10 100 13 180 1055 10 17 13 180 1059 10 20 6 180 1059 10 21 6 180 1067 10 22 6 180 1067 10 23 6 180 1082 10 24 6 180 1082 10 25 6 180 1090 10 26 A 6 180 1097 10 26 B 6 180 1097 10
27 6 180 1097 10 28 6 180 1116 10 29 6 180 1120 10 33 8 90 1189 4 34 8 90 1176 4 35 8 90 1173 4 36 8 90 1173 4 u 0 CO O 9 0 V ,0 - vol CO -1 0343 91 oo CO V CO OD tri ry syl CO N av .0 co 4 vs Q 0. O NI 0 .0 CO cr vy O. VI 4, VD /V v, VII 4,
115 <5 45 866 29 116 <5 45 866 29 92 3 315 872 4 103 5 270 777 18 20 0 1097 9 102 20 0 1109 9
105 5 0 823 1
106 6 0 811 1
107 6 0 811 1 109 6 0 805 2 118 6 0 805 2 119 5 0 805 2 120 5 0 805 2 123 5 0 798 2 121 5 270 960 9 124 2 225 926 10 125 2 225 926 10 127 2 225 922 10 128 2 225 917 10 129 2 225 917 10 130 2 225 922 10 131 2 225 922 10 132 2 225 926 10 133 2 225 926 10 134 17 0 1029 9